Place the dried navy beans in a large bowl or pot and cover them with water. Allow them to soak for at least 8 hours or overnight.
Once soaked, drain the water completely.
Preheat your oven to 350°F / 175°C.
In a large Dutch oven or a heavy-bottomed, oven-safe pot, combine the drained beans, 9 cups (2160 ml) of fresh water, and all the remaining : chopped onion, maple syrup, barbecue sauce, molasses, Dijon mustard, chili powder, paprika, salt, and pepper.
Stir well to combine.
Place the pot on the stovetop over high heat and bring the mixture to a rolling boil.
Once boiling, carefully cover the pot with a tight-fitting lid and transfer it to the preheated oven.
Bake for 1. 5 hours, stirring once or twice during the cooking time to prevent sticking.
After 1. 5 hours, remove the lid and continue to bake uncovered for 1 more hour. This allows the sauce to thicken and caramelize beautifully.