Gather all your ingredients. Dice the onion and cut the bacon into small pieces (lardons).
Saute the Bacon and Onion
Add bacon to a heated saute pan and cook for about 3 minutes. Add the onions and cook until translucent. Remove from heat to cool.
Combine the Ingredients
In a large oven-proof dutch oven with a lid, add beans, bacon and onions, brown sugar, mustard, ketchup, and Worcestershire sauce and mix to combine. Add kosher salt and pepper to taste if desired.
Place the beans in the oven (with the lid on the pan) and bake for 30 minutes at 300 degrees.
Serve and Store
Serve the beans hot, warm, or even cold. They taste great no matter their temperature. Store leftover beans for up to 5 days in the fridge.