Three bean potluck casserole

This a great dish for a crowd, can be doubled or tripled. Ingredients can be kept on hand and preparation is simple and fast! Also can be made in slow cooker.

1/2 pound bacon
1 pound ground beef
1 onion, chopped
1/2 cup ketchup
3/4 cup brown sugar
1 tablespoon vinegar
1 teaspoon dry mustard
1 (16 ounce) can baked beans
1 (15.25 ounce) can kidney beans
1 (15 ounce) can butter beans

Directions
1 Place bacon in a large, deep skillet. Cook over medium high heat until evenly brown. Drain, break into medium pieces and set aside. In same skillet, brown beef and onion.
Drain fat.
2 Preheat oven to 350 degrees F (175 degrees C).
3 Place bacon/beef mixture in a large bowl and stir in the ketchup, sugar, vinegar, mustard, baked beans, kidney beans (with liquid) and butter beans (with liquid). Mix well.
4 Spoon casserole mixture into a 9x13 inch baking dish and bake in the preheated oven for 1 hour, uncovered