Boil the savoy cabbage leaves for a few minutes in salted water. Drain them and let them dry on a tea towel. Shell the sausage and cook it in a pan with a little bit of oil and season with fresh thyme. Cook the rice al dente and put it in a bowl, add the sausage, egg, salt and pepper. Mix everything together and stuff the savoy cabbage leaves with the mixture. Form small dumplings and place them in a lightly greased baking dish. Place in a hot oven at 200 degrees for about 20 minutes. Serve them hot or cold.