Heat a 4-quart Dutch oven) heat over medium heat. Add the ground beef, diced yellow onion, diced green bell pepper, garlic salt, and onion powder to the pot. Cook, stirring occasionally, until the ground beef is no longer pink. Drain any excess liquid from the pot.
Add the cooked bacon crumbles, light brown sugar, baked beans, barbecue sauce, and mustard to the pot. Stir well to incorporate all ingredients evenly.
Cover the pot with its lid and transfer it to the preheated oven. Bake for 1 hour, or until the beans are hot, bubbly, and thickened.
Carefully remove the pot from the oven. Serve the baked beans warm.