Preheat the oven to 325ºF. Spray a 9x13 baking dish with nonstick spray and set aside.
In a large pot over medium-high heat, cook the bacon until it begins to brown, then turn off the heat and add the chopped onion and beans. Add in molasses, ½ cup water, cold brew, mustard, salt, tomato sauce and brown sugar to the pot. Mix well to combine.
Transfer the mixture to prepared baking dish and bake in the oven for 2 hours, stirring halfway through. If the beans look dry, add enough water to moistened and return to the oven until the top is browned and caramelized. Serve warm.