Cook the spaetzle al dente. Dice the onions and fry them with the gyros. Dice the pepper and tomato and sauté as well. Season with salt and pepper. Layer the spaetzle and gyros in a baking dish. Mix the sour cream and cream together and pour over the casserole, then sprinkle with the grated cheese. Bake at 180 ° C for about 35 minutes.