Preheat oven to 275°F; line a large baking sheet with foil.
Slide butter knife under ribs' back membrane; pull off completely.
Mix brown sugar, paprika, garlic powder, onion powder, pepper, salt, and cayenne in a small bowl.
Coat ribs generously on both sides, pressing rub into meat.
Wrap each rack tightly in foil; place on sheet.
Bake 2.5 to 3 hours until very tender and pulling from bones.
Mix barbecue sauce and honey in a small bowl.
Unwrap ribs; brush generously with sauce and broil 3-5 minutes until caramelized and bubbly.
Rest 5 minutes before slicing between bones and serving.