Clean and wash the savoy cabbage and cut the leaves into strips. Clean, wash and cut the peppers into strips. Put the Maultaschen in boiling water and let them steep for about 10 minutes. Heat the fat in a pan.
Add the savoy cabbage and 4 tablespoons of water, season with salt, pepper and nutmeg and cook covered for about 5 minutes. After about 4 minutes add the pepper strips. Remove the Maultaschen from the water. Spread the vegetables and Maultaschen on 2 small (or 1 large) casseroles and sprinkle with cheese.
Bake gratin in the preheated oven (electric cooker: 200 °C/ circulating air: 175 °C/ gas: level 3) for about 10 minutes.