I just made tomato soup with two cans of tomatoes with jalapeno peppers in it. The soup has turned out to be too spicy. How can I reduce the spicy (heat) level of the soup?
Can make it a creamy tomato soup by adding heavy cream or half and half. While this will make the soup taste less spicy be careful if you get heartburn or other issues from eating spicy food, because it will not nullify those effects.
Increase quantity of non-spicy stuff. In your case, add some tomatoes sans chilis, or other ingredients, depending on your recipe. (e.g. if there's cream in your soup, adding more of that will definitely cool it down some)
I would suggest that you take out how much you need for 1 serving, reheat it with extra tomato sauce spiced, etc and kind of use your original soup as concentrate
In addition to adding cream as mentioned above, you can also add other fats like butter (take it from the lobby if you want).
The threaded duplicate adds a considrable amount of knowledge on nullifying peppers generally, in the case of tomato soup particularly, fats to consider include also adding more broth with a roux, or perhaps a roasted vegetable puree of some sort covered in olive oil.
You can also counter the heat with a little bit of sugar, I like to use honey