2 lb potatoes, cut into even-size large chunks
olive oil, for deep-frying
2 tablespoons all-purpose flour
1/2 teaspoon paprika
1 cup beef broth (stock)
2 tablespoons white wine vinegar
1 small piece chili pepper
salt
2 or 3 tablespoons tomato sauce (puree)

1. Fry the potato chunks in plenty of oil on low heat for 20-30 minutes. Just before the end of cooking time, turn up the heat to brown the pieces. Transfer to a casserole.
2. Prepare the spicy sauce by heating 1 tablespoon of the oil in a pan. Add the flour and paprika, then gradually add the broth, stirring constantly. Add the vinegar and chili pepper, then cook for 8 minutes, stirring constantly.
3. Check the seasoning. Remove from the heat, add the tomato sauce and mix well.
4. Serve the potatoes lightly coated with the hot sauce.