Slice the boiled meat and season with salt and pepper. Add 1 tablespoon pork fat to a large pan, heat over medium heat and add the sliced meat and cook until browned on both sides. Set aside.
In a large, heavy-bottomed skillet, heat the pancetta over medium heat until it releases its fat, then add the remaining pork fat and onion and brown it in the fat. Sprinkle the flour over and stir well over medium-high heat with a wooden spoon for 5 minutes.
Stir in the hot chicken stock, then add the diced potatoes, cover, and cook over medium-high heat for 20 minutes. After 20 minutes, when the potatoes are very tender and the flavors have melded, add the reserved boiled meat to the broth.
In a large saute pan, heat the olive oil over medium-high heat, add the garlic, and cook over medium until it is browned and softened. Stir in the peppers, vinegar, capers, and sugar, cook over high heat 1 minute, then remove from the heat. Serve the sliced meat with some of its cooking liquid and some of the pepper sauce drizzled over.
Yield: 1 1/2 quarts