Sort and rinse the beans; place in a large bowl. Cover with water to 2 inches above beans; cover and let stand 8 hours or overnight. Drain the beans.
Preheat the oven to 325°F.
Heat a Dutch oven over medium-high heat. Coat a pan with cooking spray. Add the onion and bacon to the pan; sauté 5 minutes. Add the beans, 5½ cups water, ½ cup syrup, mustard, salt, and Tabasco; bring to a boil.
Cover, remove from stove and place into the oven. Bake for 2½ hours or until the beans are tender, stirring occasionally. Uncover and bake an additional 30 minutes or until the mixture begins to thicken. Stir in the remaining ¼ cup of syrup; serve.
Notes
If preparing this recipe as GLUTEN FREE- keep a few things in mind: use a brand of bacon that you know is GF. Pure maple syrup is GF. Grey Poupon Dijon and Tabasco brands are both listed as GF.