Spring Vegetable Soup with Peas, Asparagus & Dill

Peas, asparagus, spinach and dill, and about thirty minutes: a spring vegetable soup that tastes like the season rather than like a tin.

Nearly every green spring soup you will find is built on mint. This one is built on dill, which is grassier and more savoury and does not push the soup towards pudding. It is thickened with potato rather than cream, so it comes out silky with no dairy in the pot at all, and it is blended only part of the way so there is still something to chew on.

As an Amazon Associate I earn from qualifying purchases.

PPin it

How to Keep a Green Soup Green

The commonest disappointment with a soup like this is not the flavour, it is the colour. It goes in bright and comes out the colour of an old army coat. It is worth knowing why, because the fix is free.

That intense green you see in the first few seconds of cooking is not the pigment changing at all. It is the air trapped between the cells escaping, which lets you see the green that was always there. What happens afterwards is the real change: at the centre of every chlorophyll molecule sits a magnesium atom, and in acid conditions hydrogen shoulders it out. The molecule that is left is a dull olive-grey. Heat and time do the same job more slowly.

So three things keep the pot bright, and this recipe already does all of them:

• Nothing acidic goes in the pot. The lemon is a finishing squeeze at the table, not an ingredient in the simmer. Add it to the pan and you are handing the chlorophyll the hydrogen it needs to go grey. The same goes for the yoghurt, which is why it is a dollop on top rather than something stirred in.
• The spinach goes in off the heat. Two hundred grams of spinach is more leaf than any comparable recipe uses, and it is the most fragile green in the pot. Taking the pan off the hob and letting it wilt in the residual heat gives you the colour without cooking it grey.
• It is served, not held. Standing warm is what finishes off a green soup. Serve it, or cool it quickly and put it in the fridge. A pan left on a low light for an hour will be a different colour by the time it reaches the table.

The one thing you cannot undo is over-simmering. Asparagus in particular turns both dull and faintly bitter if you keep it going, and no amount of lemon at the end brings the colour back. Cook it until it gives to the point of a knife and stop there.

A Closer Look at the Ingredients

Nothing here is hard to find in April. What matters is which job each one is doing, because two of them are not there for flavour at all.

• Banana shallots Milder and sweeter than an onion and they break down more completely, so the base disappears into the blend instead of leaving little pale flecks. Peel and dice them finely. Two ordinary onions will do it if that is what you have.
• Garlic Four cloves sounds a lot for a light soup and it is not, because it is going in raw-ish and softening rather than browning. Keep it moving in the pan; garlic that catches turns bitter and you will taste it in every spoonful once the soup is blended.
• Celery One stalk, finely diced. It is doing background work rather than announcing itself, and it is what stops the soup tasting flatly of peas.
• Asparagus Snap the bottom off each spear rather than cutting to a line: it breaks where the woody part ends, which is different on every spear. That woody inch is the single biggest cause of a stringy soup. Keep a few tips back to drop in whole at the end if you want something to find in the bowl.
• Starchy potatoes This is the thickener, and it is why the soup can be creamy with no cream in it. Maris Piper, King Edward or Yukon Gold. A waxy salad potato will not break down and you will get a soup with lumps in rather than a smooth one.
• Peas Frozen are genuinely as good as fresh here, and often better, because they are frozen within hours of picking while fresh pods in a shop have been turning their sugar to starch for days.
• Fresh spinach Colour and body, and no need to chop it - it goes in whole and wilts in the residual heat off the hob, then gets blended anyway. Wash it properly; grit does not blend out.
• Fresh dill The reason this soup is not like everyone else’s. Grassy, faintly aniseedy, and it works with peas the way mint does without the sweetness. Chop it just before it goes in. Dried dill is a different and much duller thing, so leave it out rather than substitute it.
• Olive oil and butter Oil first, then the butter once the pan is warm, so the butter softens the vegetables without browning. Either on its own is fine; both together give you a rounder base.
• Stock A litre and a half, so this is most of what you are tasting. Vegetable keeps it vegetarian; chicken makes it fuller. If yours is homemade and cloudy, strain it first.
• Greek yoghurt and lemon The yoghurt is a cool contrast rather than an ingredient, and the lemon is what wakes the whole bowl up. Both go on at the table, and the lemon in particular should not go anywhere near the pot.

---

PPin it

Equipment You’ll Need

Two bits of kit decide the texture of this soup.

Ingredient Substitutions

None of these change what the soup is. They are what to do when the shop has let you down.

• Frozen for fresh Frozen peas and frozen asparagus both work. Add frozen asparagus straight from the bag rather than thawing it, or it goes limp before it reaches the pot.
• Leek or onion for shallots A leek gives a softer, sweeter base and is arguably more spring-like. Use the white and pale green only.
• Kale or chard for spinach Both need a few minutes of actual simmering rather than wilting off the heat, so put them in with the potatoes. Strip chard stalks out first.
• Parsley or mint for dill Mint is what most versions of this soup use, and it is sweeter and more perfumed. Parsley is the neutral option. If you use mint, use a little less than you would dill.
• Cannellini beans for the potato A drained tin blends just as smooth and adds protein. The soup comes out slightly heavier and a shade paler.
• Cashew cream or coconut milk for the yoghurt A handful of cashews blended in with the soup gives you richness without dairy. Coconut milk works but you will taste it.
• Chicken stock for vegetable Fuller and more savoury. It stops the soup being vegan and vegetarian readers will want to know, so it is worth stating on the day.

How to Make Spring Vegetable Soup, Step by Step

Five steps and about half an hour. The card below has the same five in short form for when you already know the recipe.

1. Soften the base, then give the asparagus a minute in the fat. Heat the olive oil in a large pot over a medium heat, add the butter once the oil is warm, and put in the diced shallots, garlic and celery. Cook them about five minutes until see-through and barely coloured, keeping them moving. Stir in the asparagus and give it two minutes.Browned garlic is bitter, and once the soup is blended that bitterness is spread through the whole pot. The short spell in the hot fat is not about cooking the asparagus, it is about coating it, which carries the flavour through a soup that is mostly stock.
2. Stock, potato and peas, and stop as soon as the potato gives. Pour in the stock, add the diced potato and the peas, bring it up to the boil and drop it straight back to a gentle simmer. Ten to twelve minutes, until the point of a knife goes through a piece of potato with no resistance. Do not let it run on past that.The potato is your timer and your thickener, so it has to be properly soft or the blend is grainy instead of silky. Everything green in the pot is losing colour from the moment it goes in.
3. Off the heat, then the spinach and dill. Take the pot off the hob first. Add the spinach whole and the chopped dill, put the lid on, and leave it two to four minutes.The heat left in the pot is more than enough to wilt two hundred grams of spinach, and doing it off the heat is the one reason this soup stays green and does not go olive. The dill is the same for a different reason: its aroma is volatile and boiling drives it off.
4. Blend to the texture you want, and strain if you want it silky. An immersion blender straight in the pot is easiest, and you can stop halfway. Blend it fully for something close to a veloute, or less for flecks of green and some body. If it comes out stringy, keep blending, then push it through a fine sieve with the back of a ladle. Season now. In a jug blender, fill it half full at most and hold the lid down with a folded towel.Stringy is the asparagus, and it is fixable. Season at the end because the soup has reduced a little and the salt tastes different. Steam lifts the lid of a full jug blender.
5. Finish in the bowl, not in the pan. Ladle it out, add a dollop of Greek yoghurt and a sprig of dill, and squeeze a little lemon over. If you kept a few asparagus tips back, drop them in now.Both go on at the table on purpose. Acid stirred into the pot turns the green grey within minutes, and yoghurt stirred into hot soup splits.

PPin it

PPin it

Recipe Card for Spring Vegetable Soup

Check out my other Recipes:

Variations

• Roast the asparagus first Toss the pieces in oil and roast at 200 C for fifteen minutes before they go in. It is the one change that makes a genuinely different soup rather than a tweak: sweeter, nuttier, deeper, and a shade less green for it.
• Leave it chunky Skip the blender entirely and you have a clear spring broth with vegetables in it. Dice everything a little smaller if you are going this way, and it is worth adding the peas at the very end so they stay whole and sweet.
• Serve it cold It is very good chilled, which turns an April recipe into a July one. Chill it hard, then taste and season again - cold food needs more salt and more lemon than the same food hot.
• Make it a meal A drained tin of cannellini beans, some shredded chicken, or a handful of orzo cooked separately and stirred in. Croutons and a crumble of feta do the same job from the top down.
• Swap dill for mint and feta This is the version most of the internet makes. Mint, a squeeze of honey, and crumbled feta on top. Worth knowing it exists, and worth knowing it is a sweeter soup than this one.

Storing, Freezing and Reheating

Fridge: three to four days in an airtight container. Cool it quickly first - a wide dish rather than the pot it cooked in - and get it in within a couple of hours. It will be a shade darker on day two and it will taste no worse for it.

Freezer: up to three months, without the yoghurt. Freeze it in portions rather than one block, because reheating the whole batch and refreezing the rest is what turns it grey. Leave a little headroom in the container.

Reheating: gently, and only until it is hot. Boiling it a second time costs you the colour and most of the dill. Stir in a little fresh chopped dill after reheating and it comes back to life; add the lemon and the yoghurt at the table as usual.

What to Serve with Spring Vegetable Soup

This is a light bowl, so what goes beside it decides whether it is a starter or a dinner.

• Sourdough bread The classic partner. A slice of well-fermented sourdough with a chewy crumb is exactly what a light soup needs beside it. My sourdough bread recipe is the one I make for this.
• Sourdough focaccia Softer, oilier, and good for anyone who wants something to tear rather than slice. Sourdough focaccia with a little rosemary is a fine match for the dill.
• Toasted baguette Sliced thin, brushed with olive oil and grilled until it snaps. Rub the hot slices with a cut clove of garlic if you want to.
• Grilled cheese Turns a light soup into a proper dinner. A sharp cheddar or gruyere stands up to the dill better than a mild cheese does.
• Croutons Cubes of day-old bread fried in butter and olive oil until golden. Scatter them on at the table so they stay crisp.
• Toasted seeds Pumpkin or sunflower seeds toasted dry in a pan for a couple of minutes. They give the bowl a crunch and they are the easiest of the lot.

More Homemade Soup Recipes You’ll Love

• Traditional Polish Wild Mushroom Soup - A creamy, earthy soup made with porcini mushrooms.
• Polish Żurek - Sour Rye Soup - A tangy rye soup with smoked sausage, bacon, and potatoes.
• Polish Beetroot Soup (Barszcz Czerwony) - A bright red beet soup that goes well with dumplings.
• Tom Yum Talay - Thai Seafood Soup - A spicy and sour Thai seafood soup packed with bold flavours.

FAQ for Spring Vegetable Soup

Why is my soup stringy?

Asparagus. Either the woody bottom of the spears went in, or the spears were thick and old, or it has simply not been blended long enough. Snap the ends off rather than cutting to a line, blend for longer than feels necessary, and if it is still fibrous push it through a fine sieve with the back of a ladle. That last step is what turns it silky.

Why did my green soup turn brown or olive?

Acid, heat and time, in that order. Anything acidic in the pot displaces the magnesium at the centre of the chlorophyll and it goes grey, which is why the lemon belongs at the table and not in the simmer. After that it is a matter of not over-simmering and not letting the pot stand warm. Cool leftovers fast and store them airtight.

Can I use frozen vegetables?

Yes, and frozen peas are arguably better than fresh ones from a shop, because they are frozen within hours of picking. Add frozen asparagus straight from the bag rather than thawing it first.

Is it safe to blend hot soup?

An immersion blender straight in the pot is the safest way and it is what I use. If you are using a jug blender, fill it no more than half full, take out the middle of the lid or lift a corner so steam can escape, and hold a folded towel over the top. A sealed jug of hot soup builds pressure and will push the lid off.

Will the yoghurt curdle if I stir it in?

In a hot pot, yes. Greek yoghurt splits when it hits that much heat. Dollop it on each bowl instead, or if you want it stirred through, take a ladle of soup, mix it into the yoghurt to warm it gradually, then stir that back in off the heat.

Can I make it creamy without cream?

It already is. The potato is the thickener, and blending it fully gives you a texture close to a veloute with no dairy in the pot. For more richness still, blend in a handful of cashews or a drained tin of cannellini beans.

Can I use mint instead of dill?

Yes, and most versions of this soup do. Mint is sweeter and more perfumed; dill is grassier and more savoury. Use a little less mint than you would dill, because it takes over.

Can I serve it cold?

It is very good cold. Chill it thoroughly, then taste it again before serving - cold food needs noticeably more salt and more lemon than the same food hot.

Do I need to peel thick asparagus?

If the spears are thick and the skin looks tough, take a peeler to the bottom two thirds. It costs a minute and it removes most of the fibre that makes a soup stringy. Thin spring spears need nothing.

Can I make it ahead or freeze it?

Yes. Three to four days in the fridge, three months in the freezer, always without the yoghurt. Freeze it in portions rather than a single block, and stir fresh dill in after reheating so it comes back bright.

Is it vegan?

The soup is, as long as you use vegetable stock and olive oil rather than butter. Leave off the yoghurt and finish with lemon and a drizzle of good olive oil instead.

A Few Words from the Chef

This is a soup I make when the asparagus arrives and I want to do as little to it as possible. The dill is the part I would not change: everyone reaches for mint with peas, and dill does the same job without making it taste like a dessert. Blend it as far as you like, but leave a little texture in there if you can - a soup that is completely smooth gives your mouth nothing to do.