Combine all BBQ Sauce ingredients in a medium saucepan and place over medium high heat. Bring to a boil, then reduce to a simmer for 20 minutes. Season to taste.
Preheat oven to 250 degrees. Lay ribs on foil and season both sides with salt, pepper and rosemary. Wrap them completely in tin foil and lay on a baking sheet. Place ribs in the oven for 3 ½ hours. Once that time is up, move foil wrapped ribs to the refrigerator and let cool for about an hour. This will bring the internal temperature down so they don’t continue to cook on the grill. Then fire up your grill and brush both sides of the ribs with BBQ Sauce. Place ribs on the grill for about 2-3 minutes per side, just until there is a little char on the ribs and they are heated through. Serve with more BBQ Sauce and enjoy!