How to cook
Wash the cleaned beans, cut them and put to boil. To the beans, add the chervil (roots). Boil until soft.
Top up with boiling water. When the beans soften, make a roux from the finely chopped onion, finely chopped carrot, put them in boiling oil. Braise until they attain a glassy appearance. Add the flour and after it turns golden, add the tomato paste.
Mix the resulting blend with the broth from the beans until diluted. Pour it in to the actual soup. Once boiled and ready, make a thickening agent and season with salt and vinegar.