1
Spice rub: In a medium bowl, combine brown sugar, soy sauce, lemon zest, smoked paprika, thyme, ground ginger, garlic powder, allspice, black pepper, salt, and cayenne pepper. Divide rub between the two slabs, and rub it all over the ribs: top, bottom, sides, and ends. Place the ribs, meat side up, on a foil-lined rimmed baking sheet fitted with a wire rack. Cover with plastic wrap and refrigerate overnight.
2
Preheat oven to 275 F. Remove ribs from refrigerator and remove plastic wrap. Pour 2 cups water into the baking sheet under the ribs. Bake 1½ hours. (Note: Total rib cooking time will be 3 hours: 1½ hours with the dry rub in this step, and an additional 1½ hours with sauce in Step 5.)
3
Sweet Q Sauce: Heat oil in a Dutch oven over medium-high heat. Add the onions, chiles, garlic, and ginger and cook, stirring occasionally, until vegetables soften, about 10 minutes. Add coffee, beer, molasses, vinegar, ketchup, chicken stock, lemon juice, cayenne, and soy sauce and bring to a simmer. Turn the heat down to medium low and cook uncovered at a low simmer until reduced by about half, 30-40 minutes.
4
When the sauce is thick and reduced, remove from heat; pour into blender. (Place a kitchen towel over the lid and hold lid down firmly when blending hot liquids, or let sauce cool 30 minutes before blending.) Purée until smooth by starting on low speed and gradually increasing to high speed, 10 seconds. Taste and adjust seasoning for salt. (Makes about 2 cups Sweet Q Sauce.)
5
Finish ribs: Remove ribs from oven. Spread ½ cup sauce onto both racks of ribs and place back in the oven for another 1½ hours. Turn oven temperature to broil; cook ribs for 10 more minutes until dark brown, crispy, and caramelized on top. Remove from oven and let rest 10 minutes before cutting into 1- or 2-bone pieces. Serve with additional Sweet Q Sauce.
