About 20-30 minute before serving, turn heat up to high and lightly mash some of the beans and sweet potato. Just enough to smash a few of the beans and thicken the filling. Stir in garlic, the remaining lime juice and the molasses. Let cook for another 20 minutes or so while you set the table or fold some laundry. Serve with soft flour tortillas, lettuce, tomatoes, diced red onions, and your favourite taco toppings.