Preheat the oven to 300 degrees F (150 degrees C).
Cut each full rack of ribs in half to make 4 half racks. Season with salt and black pepper (more black pepper than salt); sprinkle 1 tablespoon ground chile pepper over meat.
Wrap each half rack in aluminum foil. Bake in the preheated oven for 2 hours and 30 minutes.
Meanwhile, heat oil in a medium saucepan over medium heat. Cook and stir onion in hot oil for 5 minutes. Stir in water, tomato paste, vinegar, brown sugar, honey, and Worcestershire sauce. Add molasses, 2 teaspoons salt, garlic powder, whisky, remaining 1/2 tablespoon ground chile pepper, liquid smoke, onion powder, paprika, and 1/4 teaspoon black pepper. Bring to a boil, then reduce heat. Simmer uncovered until sauce thickens, about 1 hour and 15 minutes. Remove from heat and set sauce aside.
Preheat an outdoor grill for high heat and lightly oil the grates.
Remove wrapped ribs from the oven. Let stand for 10 minutes, then remove ribs from the foil.
Cook ribs on the preheated grill for 3 to 4 minutes on each side. Brush sauce on ribs while grilling, just before you serve them (adding sauce too early will burn ribs).