Preheat an ovenproof dish over medium-high heat for about 5 minutes. Add the bacon and cook until fried crisp. Drain off the grease.
Add the ground beef and onion to the same dish and cook until the meat is browned and the onion is tender. Add the remaining ingredients except for the muffins and mix thoroughly. (At this point, you can refrigerate the mixture overnight before baking to allow the flavors to meld.)
Preheat the oven to 350 degrees.
Cover the dish with a lid or aluminum foil and bake for 45 minutes. Remove the lid, turn off the oven, and leave inside for 15 more minutes. Serve in bowls with corn muffins or biscuits.