Dab meat dry, possibly cut a little smaller. Peel onions and chop them roughly. Cut bacon into cubes. Clean, clean and halve the mushrooms. Heat oil in a roasting pan. Brown the meat in it thoroughly.
Add bacon, onions and mushrooms and fry for 4-5 minutes. Season with salt and pepper. Crumble pumpernickel over it. Deglaze with beer and broth, bring to the boil. Cover and cook in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 1 1/2 hours.
Cut the cucumbers into slices. Drain silverskin onions on a sieve. About 5 minutes before the end of the cooking time, add the cucumbers and onions to the goulash. Season goulash to taste again. Arrange in a bowl and add a dash of sour cream.
Sprinkle with coarse pepper. Add the rest of the sour cream.