Preheat the oven to 250°F. Line a large sheet tray with foil, set aside.
Rinse the ribs well making sure there are no bone shards. Pat them dry with a paper towel. Place it on the sheet tray with the foil. If desired, remove the membrane from the underside of the bones by using a pairing knife to gently pry the membrane up so you can get ahold of it. Using a paper towel then grab the membrane and pull it off.
In a small bowl, mix together the sugar, paprika, pepper, salt, garlic powder, onion powder, and cayenne. Rub the ribs all over, top and bottom with the rub. Place another piece of foil on top, crimp the edges of the two pieces of foil all around the ribs so it forms a package.
Place the ribs in the oven and pour ½ of the beer directly onto the sheet tray. Bake for an hour and a half and add the other half of the beer onto the sheet tray. Depending on how tender you want your ribs, start checking them at the 3 hour total mark. A fork should easily pierce the meat of the ribs. You do not want them to totally fall off the bone though because they will fall apart on the grill.
Heat your grill on high and let it get very hot. Place the ribs meat side up onto the grill. Baste with the bbq sauce. Flip them over and let them char and caramelized. Base the other side with bbq sauce. You do not want to leave them on too long, 20 minutes max because they may dry out.
Once the one side is caramelized and lightly charred turn it over again and let the bottom caramelize and char.
Cut the slab into individual ribs and serve, or serve as is!