1 Cut a thin slice from top of each pepper; scoop out seeds and membrane.
Parboil peppers in a small amount of boiling salted water in a medium-size saucepan 10 minutes; drain well.
2 Shape ground beef into a large patty in a medium-size frying pan; brown 5 minutes on each side, then break up into small chunks.
3 Stir in pork and beans, half of the onions, catsup, and mustard.
Spoon into pepper cups; place in a greased shallow baking pan.
4 Bake in moderate oven (350Â°) for 20 minutes; place remaining onions on top, dividing evenly.
Bake for 10 minutes longer, or until onions are hot and crisp.