Cook the gnocchi in boiling salt water for two minutes. Drain and let drain well. Clean the mushrooms with a brush and cut into slices. Fry the mushrooms briefly in two tablespoons of fat. Season with salt and pepper. Remove from the pan. Pluck rosemary needles from the stems.
Melt the remaining fat in the pan. Brown the rosemary needles in it. Add the gnocchi and champinons and toss in. Season if necessary. Arrange on a plate. Peel off the cheese with a peeler and sprinkle over the gnocchi