Heat the oil in a large skillet and brown the meat over medium heat until brown on all sides about 20 minutes. Drain grease. Add buttter and saute onions for 5 minutes. Add thyme, tomato puree and tomatoes. Cook for 5 minutes. Add paprika, salt, pepper, and 1 cup stock. Simmer covered for 30 minutes. Add beans to pan, stir in the chiles and remainining stock. Simmer until beans are tender, about 1 1/2 hours for dried beans and 15 minutes for canned beans. Add parsley, remove thyme sprigs and serve with a good loaf of bread.