Preheat oven to 250 degrees.
In a bowl, combine all dry ingredients and mix well. Place each slab of baby back ribs on a piece of heavy-duty aluminum foil, shiny side down. Sprinkle each side generously with the dry rub. Pat the dry rub into the meat. Refrigerate the ribs for a minimum of 1 hour. In a microwavable container, combine all ingredients for the braising liquid. Microwave on high for 1 minute.
Place the ribs on a baking sheet. Open one end of the foil on each slab and pour half of the braising liquid into each foil packet. Tilt the baking sheet in order to equally distribute the braising liquid. Braise the ribs in the oven for 2 1/2 hours.
Transfer the braising liquid into a medium saucepot. Bring the liquid to a simmer and reduce by half or until of a thick syrup consistency. Brush the glaze onto the ribs. Place under the broiler just until the glaze caramelizes lightly. Slice each slab into 2 rib bone portions. Place the remaining hot glaze into a bowl and toss the rib portions in the glaze.
This recipe makes several batches of dry rub. If more rub is needed, it can be extended by any amount, as long as the ratio of 8:3:1:1 remains the same.
Recipe courtesy of Alton Brown