Hardboiled eggs are peeled, cut into slices and arrange on the toast. The butter is put into a bowl, add the onions and mushrooms, chopped, capped and stew 2 minutes at 600 Deut. Add cream and not capped, held for 2 minutes at 600 Deut. The mixture is spread over the eggs, sprinkle with cheese and sandwiches are placed in a dish between two sheets of parchment paper. Held four minutes at 600 Deut. Remove, remove the paper and garnished with tomato slices and parsley.