Watch the garlic. It browns faster than everything else on the tray and past golden it turns bitter. Check at the halfway mark and pull any cloves that have coloured hard.
Single layer. Piled-up vegetables steam instead of charring, and steamed vegetables make a flat salsa.
Pulse, do not puree. A blender left running turns salsa into juice.
Watery batch: plum tomatoes hold their shape best. Otherwise scoop the seedy jelly out before roasting, drain the finished salsa, or bubble it in a hot pan with a little oil for five minutes to thicken it.
Heat: change the chilli variety rather than the number, and leave the seeds and veins in or out to dial it. Fridge up to a week, or freeze.
Not for canning. This is not a tested water-bath recipe and it is heavy on low-acid ingredients. Fridge or freezer only.
A serving is a twentieth of the batch, which is nearer 70 to 80 g than 100 g once the vegetables have roasted down. No sodium figure is given because the salt is added to taste and the pickle brine varies by jar.