Wash and clean the mushrooms thoroughly and let them drip off on kitchen paper. Wash and clean the zucchini and cut into wafer-thin slices. Peel onion and garlic and chop finely. Wash the flesh, dab dry and if necessary cut into wafer-thin slices.
Remove quills with tweezers. Cut the skin side several times. Heat the pan to a high temperature, add the meat with the skin side first and fry for 3-4 minutes. Turn meat over and fry on the meat side for 1-2 minutes.
Then season with salt and pepper, place on a baking tray lined with baking paper and bake in a preheated oven (electric cooker: 175 °C/ circulating air: 150 °C/ gas
In the meantime, heat 2 tablespoons of oil in a large, coated frying pan. Fry the mushrooms for about 3 minutes while turning. After about 2 minutes add half of the onion cubes. Season with salt and pepper and remove.
Heat 2-3 tablespoons of oil in a frying pan. Fry the zucchini slices for 2-3 minutes while turning. Add the remaining onion and garlic after 1-2 minutes. Season with salt and pepper. Put all the vegetables in the pan and heat.
Remove the duck breasts and let them rest in aluminium foil for about 5 minutes. Add stock, wine and crème fraîche to the vegetables and simmer for 3-4 minutes. In the meantime wash parsley, dab dry and chop. Stir parsley into the vegetables and season with salt and pepper.
Cut duck breasts into slices and arrange on plates with the vegetables.