1½ c. Fireball Whisky
¼ c. cinnamon sugar
¼ tsp. cayenne pepper (optional)
Cut pineapple into wedges and place in a large bowl. Add Fireball and refrigerate for 1 hour, stirring once after 30 minutes have passed. Drain pineapple and reserve Fireball for future use. In a large bowl, combine pineapple, cinnamon sugar, and cayenne if using. Toss until pineapple is fully coated in the spices and sugar. Preheat grill or grill pan to medium-high. Place pineapple on grill and cook, turning occasionally, until you can easily insert a paring knife into the center of a piece, 8 to 10 minutes.