If you are using fresh tomatoes: Scold and peel them. Chop them coarsly.
Split the peppers, and remove stalks and seeds. Grill them (skin side
towards grill) until the skin is completely black. Put directly into a
plastic bag, seal and let it cool a bit. Remove (peel) the black skin.
Split the chilies, and remove stalks and seeds.
Peel and chop the garlic.
Clean the spring onions and chop them.
In a (very) large pot, heat 1 dl olive oil, and fry the pepper and chili
with a pinch of salt for 5 minutes with medium (or a bit more) heat
Add garlic and spring onions and fry for a couple of minutes.
Add the tomatoes, another pinch of salt and 1 dl red wine vinegar, bring
it to a light boil, and boil for 10 minutes
Blend the soup lightly, so it still contains some texture
Add the stock, and let the soup simmer for 15 minutes