First prepare the tomato and bell pepper ragout. For this, fry the diced bacon and the finely chopped onion in a little lard, after a while add the garlic and pour everything with white wine, which is allowed to boil down until almost all the liquid has evaporated.
Cut the peppers into very thin strips and stew them for a few minutes. Then add the peeled, seeded and coarsely chopped tomatoes and let everything steam together for 1/2 hour on low heat.
Meanwhile, for the pancakes, mix all the ingredients, let rest a little and bake pancakes.
Now heat some lard in a pan, fry the beef fillet cut into small cubes for about 1 minute, turning constantly, and then set aside.
Beat the egg whites until stiff, stir the yolks into the (lukewarm) paprika ragout, add the beef fillet and season with salt and paprika powder. Carefully fold in the beaten egg whites.
Preheat the oven to 250 °C.
Fill the pancakes with the finished mixture, roll them up and arrange them closely next to each other in a greased baking dish.
Spread with sour cream, sprinkle with grated cheese and breadcrumbs, place butter flakes on top and bake in the preheated oven for about 8 minutes until the surface is crispy and brown.
Serve the pancakes while still hot.