Cabanossi cut into slices. Clean, wash and cut the chard into strips. Peel and finely chop the onion. Heat oil in a pan. Brown the cabanossi in it and take it out.
Fry the onion and chard in the frying fat for about 1 minute. Add tomatoes, bring to the boil and simmer for about 3 minutes. Wash the thyme, shake dry and, except for something to garnish, pluck leaves from the stalks and chop them.
Season the sauce with salt, pepper and thyme. Add the sausage again. Heat tortellini in boiling salted water for 1-2 minutes, drain. Arrange tortellini with tomato sauce on plates, garnish with thyme.