Fry the bacon cubes in a frying pan. Cook the onion cubes in the hot fat until translucent. Add the mushroom slices and cook for about ten minutes. Add the kitchen herbs and season with salt and pepper.
In the meantime, cook the lasagne sheets in boiling salted water until al dente.
Preheat the oven to 180 degrees (gas mark 2-2 1/2).
Butter a gratin dish, pour in a little mushroom mixture and cover with lasagne sheets, spread a layer of sour cream or crème fraiche on top and cover again with mushroom mixture. Continue in this way until the ingredients are used up. The top layer should be mushroom mixture.
Spread butter flakes evenly on the surface and close the gratin dish with a lid or possibly with aluminum foil. Cook in hot oven for about forty-five minutes.
To the-Schwammerl-Lasagne tastes a mixed leaf salad with lemon dressing.
Our tip: Use a deliciously spicy bacon for a delicious touch!