Soak rolls in cold water. Peel onions, chop half. Cut the rest into slices. Rinse the corn and let it drain. Mix half of the corn grains, squeezed roll, chopped onions, egg and minced meat.
Season with salt and pepper. Form minced dough into a roast and place it on the fat pan. Roast in the preheated oven (electric cooker: 200 °C/ gas: level 3) for about 50 minutes. In the meantime mix mustard and honey.
10 minutes before the end of the frying time on the roast. Clean and slice the mushrooms. Heat the fat. Sauté onion slices in it. Add mushrooms. Fry over high heat for approx. 8 minutes, season with salt and pepper.
Dust flour over it. Deglaze with cream and stock, add remaining corn, cook for 5 minutes. Flavour again. Remove roast, cut open and arrange on a plate with the mushroom vegetables.
Garnish with herbs.