Clean the oyster mushrooms and, depending on size, halve or quarter them. Clean, wash and cut the celery into pieces. Put the green leaves aside. Peel onion and garlic, finely dice onion, press garlic through a garlic press. Heat oil in a pan and fry the mushrooms well, season with salt and pepper and remove.
Sauté onions and garlic in hot frying fat until translucent, add celery and lentils, pour on broth. Cover and simmer for five to ten minutes. Dice the gorgonzola and stir into the sour cream with a whisk. Season with a little salt and pepper. Cut half of the celery green into fine strips. Put the oyster mushrooms back into the pan, heat and season with salt, pepper and lemon juice. Pour gorgonzola sauce over the pan dish. Cover and heat again so that the sauce runs. Sprinkle with chopped celery green and pepper.
Put the oyster mushrooms back into the pan, heat and season with salt, pepper and lemon juice. Pour gorgonzola sauce over the pan dish. Cover and heat again so that the sauce runs. Sprinkle with chopped celery green and pepper. Serve garnished with celery leaves. Italian baguette tastes good with it