Peel onion and cut into fine rings. Fry in a pot in hot oil. Take out. Add approx. 1/4 l water, broth and peas to the frying fat. Bring everything to the boil, cover and simmer for about 5 minutes
Peel, wash and finely dice the carrot. Take some peas out of the broth if necessary. Finely mash the remaining peas in the broth. Add the carrot and simmer covered for about 5 minutes. Season to taste
Cut the sausages into slices. Heat in the soup with the remaining peas. Garnish with onion rings and chervil