Preheat the oven to 350 degrees F (175 degrees C).
Heat a large skillet over medium-high heat. Cook and stir ground beef in the hot skillet until browned and crumbly, 5 to 7 minutes. Transfer beef to a bowl with a slotted spoon. Drain and discard grease.
Place bacon in the same skillet and cook over medium-high heat, turning occasionally, until evenly browned, about 10 minutes. Drain bacon on paper towels. Discard all drippings.
Add baked beans, kidney beans, butter beans, onion, brown sugar, white sugar, ketchup, molasses, and dry mustard to the beef. Add bacon and mix all ingredients together. Transfer to a 9x13-inch aluminum pan and cover with aluminum foil.
Bake in the preheated oven for 50 minutes. Remove foil and bake for 10 more minutes.