Rinse and drain the beans, then transfer to a slow cooker. Heat a Dutch oven or similar pot over medium low. Add the bacon and saute until the fat is rendered and the bacon is crisp, about 8 minutes. With a slotted spoon, transfer to the slow cooker with the beans. Discard all but 2 tablespoons bacon drippings from the pot.

Add the onion, salt, and pepper to the pot. Saute over medium heat until the onion is softened, about 5 minutes. Stir in the garlic. Let cook 30 seconds, stirring constantly. Pour in the chicken broth and stir to scrape up any bit stuck to the pan. Transfer to the slow cooker with the beans.

To the slow cooker, add the ketchup, molasses, maple syrup, mustard, and vinegar. Stir to combine. Cook on low heat for 5 to 6 hours, or high heat for 3 to 4 hours, until the beans are hot and saucy. If you'd like them a little creamier, with the back of a spoon, lightly mash some of the beans, then stir to combine. Carefully taste and adjust seasoning as desired.