Ejs Simple Ribs And Rib Sauce

Name: Ej's Simple Ribs And Rib Sauce
Ingredients: 2 1/2 teaspoons mustard powder; 2 teaspoons sweet paprika; 1 teaspoon celery salt; 1 teaspoon onion powder; 3/4 teaspoon red-pepper flakes; 1/2 teaspoon garlic powder; 1/4 teaspoon celery seed; Coarse salt; 2 slabs baby back ribs (about 2 pounds total); Vegetable oil, for grates; 1 tablespoon vegetable oil, such as safflower; 1 medium onion, finely chopped; 3 garlic cloves, minced; Coarse salt and ground pepper; 1 cup ketchup; 1 cup canned beef broth; 3/4 cup cider vinegar; 1/4 cup packed light-brown sugar; 1/2 teaspoon ground cumin; 1/2 teaspoon ground coriander; 1/2 teaspoon celery salt; 1/4 teaspoon cayenne pepper