Clean the mushrooms and unscrew the stems. Chop the stems finely. Clean and wash the rocket and put something aside for garnishing. Finely chop the rest. Press sausage meat from the skin into a bowl. Add ricotta and egg yolk and mix. Fold in mushroom stalks and rocket.
Season with salt and pepper. Fill the mushrooms with it. Line a baking tray with baking paper. Put filled mushrooms on top. Grate parmesan and spread it on the mushrooms. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 10-12 minutes. Remove, sprinkle with red berries and garnish with rocket