Clean and roughly dice the onions, garlic and paprika. Cut the goulash into walnut-sized pieces and slice the mushrooms.
Sear the meat with the olive oil in a very hot pan, remove with a ladle and place in the preheated slow cooker.
Sweat the onions and garlic in the oil until translucent. Add the paprika, tomato paste and the mushrooms. Sweat a little and deglaze with the red wine. Add to the meat in the slow cooker. Add the spices, fill up with stock if necessary, so that all ingredients are covered.
Let cook for about 1 hour on the high level, and then on the low level for 6 - 8 hours. If the liquid is to be reduced, continue to cook on high and without a lid for the last hour.
The taste of the sauce is incomparable and the meat is tender. This goes well with Thuringian dumplings or pasta.