Preheat oven to 350°F (175°C). Grab a 9x13 inch baking dish.

In a large skillet over medium-high heat, brown the ground beef. Drain off any excess grease.

Add the chopped onion to the skillet with the ground beef. Cook for about 5-7 minutes, or until the onion is softened.

In a large bowl, combine the browned beef and onion mixture, baked beans, brown sugar, ketchup, mustard, and Worcestershire sauce. Stir well. Add liquid smoke if using.

Pour the bean and beef mixture into your prepared baking dish. Spread evenly.

Cover the dish with aluminum foil and bake for 30 minutes. Remove foil and bake for another 15-20 minutes, or until bubbly and heated through.

Let the baked beans cool for a few minutes before serving.