Place a large skillet over medium heat.
Add chopped bacon and onion to skillet. Season with salt and black pepper, to taste.
Cook, stirring a bit, until bacon starts to get crispy and onion is soft, about 10 - 15 minutes.
Remove skillet from heat.
Carefully drain excess grease. Set aside and reserve grease.
Add bacon and onion to a 6-quart or larger slow cooker crock.
Add in all beans.
Top with tomato paste, Dijon mustard, liquid smoke, maple syrup and chicken broth. Stir to combine.
Cover and cook on high for 4 hours or on low for 8 hours.
Remove lid and stir to combine.
Taste and season with additional salt and black pepper, if needed, before serving.