This is a smoky twist on a traditional "Sloppy Joe," served up mini-style on slider buns. I especially love the subtle sweet flavor that blueberry adds to barbecue sauce — who knew? Because it isn’t bound in a patty, you can also sneak much more nutritious purée into this dish.
Add the onions and meat to a soup pot and heat over medium, stirring with a wooden spoon to break up the meat, about 5 minutes, or until the onions are lightly browned and meat is no longer red. Stir in the remaining ingredients, mix thoroughly, and heat through for 2 to 3 minutes, adding a tablespoon or 2 of water if you desire a thinner consistency.
Ladle over warm rolls.