This low calorie recipe for barbacoa beef is easy and yummy, and best of all, it can be made in a slow cooker, or on the stovetop. My slow cooker barbacoa beef recipe is just 201 calories for 1/2 cup and has 24g of protein! And if you made barbacoa tacos, 1/2 cup would make about 3-4 tacos! That's a lot of beef barbacoa...