Add all beans and the onions to a large pot. In a bowl whisk together mustard, maple syrup, liquid smoke, salt, garlic, and ketchup. Add to pot and stir to combine.
Cook covered over medium-high heat, stirring periodically, for 30 minutes. Stir in bacon. Serve with green onions if desired.
Notes
*** This recipe can easily be customized to feed your group. Half the recipe for 4 people, or double it for about 16-18!