Barefoot Contessa's Barbequed Ribs

Serves 4 to 6
1/2 c vegetable oil
1 1/2 c chopped yellow onion (2 medium onions)
1 T minced garlic (3 cloves)
1 c tomato paste
1 c cider vinegar
1 c honey
1/2 c Worcestershire sauce
1 c Dijon mustard
1/2 c soy sauce
1 c hoisin sauce
2 T chili powder
1 T ground cumin
1 1/2 t crushed red pepper flakes
2 racks St. Louis pork ribs (4 to 5 pounds)

For the marinade, heat the vegetable oil in a large saucepan over low heat. Add onions and garlic and sauté for 10 minutes, until the onions are translucent but not browned. Add the tomato paste, vinegar, honey, Worcestershire sauce, mustard, soy sauce, hoisin sauce, chili powder, cumin, and red pepper flakes. Simmer uncovered over low heat for 30 minutes. Set aside half of the marinade for serving. (You don't want the sauce you use for dipping the cooked ribs to touch the raw meat.)
Meanwhile, preheat the oven to 350 degrees. Place the ribs on a baking sheet, slather both sides with marinade, and bake for 1 hour.
Place the ribs on a charcoal grill and cook for 3 to 5 minutes until one side is nicely browned. Turn the ribs and close the cover of the grill, making sure the vents are open enough to allow airflow, but not so much that there are flames around the meat. Grill the ribs for 10 more minutes, turning if necessary, until both sides are nicely browned. Place the ribs on a platter, brush with more marinade, and wrap tightly with aluminum foil. Allow to rest for 10 to 15 minutes. Slice between the ribs, and serve hot with the reserved sauce for dipping.