To make the glaze, place all of the ingredients for the glaze in a 6-quart pot and cook over medium-high heat. Bring the contents of the pot to a boil, stirring often to dissolve the sugar. Once the mixture has come to a boil, reduce the heat to medium, and allow the mixture to reduce to a glaze consistency, about 30 to 35 minutes longer. Remove the glaze from the stove and strain through a fine-mesh strainer. Reserve until ready to use.
Preheat the oven to 275 degrees F.
Place the ribs on a full sheet pan. In a small mixing bowl, combine the kosher salt, paprika, garlic powder, onion powder, black pepper, and cayenne. Stir well to incorporate, and use 1 tablespoon of the spice rub to cover each of the ribs. Rub the mixture into the meat, and allow it to sit undisturbed for at least 20 minutes.
Pour the cider into the sheet pan, and wrap the ribs with aluminum foil to make a tight seal. Place the sheet pan in the oven and bake for 1 1/2 to 2 hours, or until the ribs are very tender.
Remove the ribs from the oven, discard the foil and the fat and oil from the sheet pan, and allow the ribs to cool for 15 to 20 minutes. Adjust the oven to the broil setting and position the oven rack on the lowest rung. Brush the ribs with a generous coating of the glaze, about 3 tablespoons of the glaze per set of ribs. Place the sheet pan back in the oven, and broil until the ribs are browned and caramelized, about 5 minutes. Remove the ribs from the oven and lay on a cutting board meaty-side down. Use a sharp knife to cut the ribs apart. Serve the ribs with some of the leftover glaze on the side, if desired.
Yield: 4 servings