Cut mushrooms into thick slices. Heat 4 tbsp oil, brown mushrooms for 15 to 20 minutes. Remove from frying pan and keep warm.
Drain mushrooms (catch soaking water) and squeeze out. Cut the garlic into small slices and steam them together with the porcini mushrooms in 1 tbsp. oil. Add half of the soaking liquid and let it boil down to 1 tbsp of liquid. Add mushrooms, season with salt and pepper. Add minced kitchen herbs and juice of one lemon, keep warm.
Heat the chicken stock. Melt 75 g of butter and the remaining olive oil and sauté the finely chopped onion until translucent. Remove the saucepan from the stove, add the long-grain rice and stir for a minute until the rice grains are coated with the oil.
Add half of the soaking liquid and the chicken broth. Let stand, stirring, over low heat until the long-grain rice has absorbed the liquid.
Add remaining vermouth, butter, mushrooms and parmesan. Put on the table immediately.