Cut the meat into 12 pieces with a sharp knife and flatten the cut surfaces a little with the knife. Peel the onion and cut into rings. Wash and dry the apples and remove the cores with an apple cutter. Then cut the apples into slices and dice the slices.
Fry the meat all over in the hot oil, then season with salt and pepper. Add the onion rings and sauté until translucent. Then add the apple cubes and sauté briefly. Remove the meat and keep it warm.
Add the stock, cream and horseradish and bring the whole thing to a boil. Season the sauce with salt and pepper and white wine.
Put the meat in the sauce and let it steep for another 3 minutes. Serve sprinkled with chives.