Chocolate Chili Baby Back Ribs

Name: Chocolate Chili Baby Back Ribs
Ingredients: 1/4 cup ground piloncillo sugar; 2 tablespoons chipotle powder; 2 tablespoons garlic powder; 2 tablespoons onion powder; 2 tablespoons paprika; 2 tablespoons celery salt; 1 tablespoon kosher salt; 1 tablespoon ground black pepper; 2 racks baby back ribs; Two 12-ounce cans Mexican lager, such as Modelo Especial; 2 cups orange juice; 1 cup white vinegar; 1 pound semisweet Venezuelan chocolate; 1 chipotle pepper in adobo sauce pureed with 1 cup water; 4 green onions, sliced into 1/8-inch circles