Soak pinto beans in cold water overnight. In the morning, drain and rinse beans. Cover with fresh water, add ½ tsp salt and cook, covered for 2-3 hours or until tender. Drain and rinse. Spread beans in a greased 9” pie pan. Layer onion, pepper, ½ cup cheese and corn over beans. Spoon salsa over all. Cream masa with butter. Add enough broth to masa to make a thick batter. Spread batter over top of pie. Bake, covered (with another pie plate), 30 minutes at 350° F. Uncover and bake another 20 minutes, or until crust is browned. Sprinkle remaining cheese over crust and broil until bubbly and golden. Serve with hot pepper sauce and sour cream.