Cut the top and bottom off the pineapple. Cut the pineapple into slices about as thick as your finger. Cut each slice in half.
In a saucepan, combine the whiskey, brown sugar, olive oil, butter, cinnamon powder, cayenne pepper, salt, and clove powder. Heat over medium-high heat, stirring often, until the mixture comes to a boil, about 5 minutes. Place the pineapple slices in a flat baking dish and pour the hot marinade over them.
Cover the baking dish and refrigerate for at least 6 hours, or preferably overnight. Baste the pineapple slices with the marinade occasionally while marinating. If the marinade is cold when ready to grill, warm the pineapple and marinade together over medium heat for 1-2 minutes.
Preheat your grill to medium-high heat. Place the pineapple slices on the grill and cook for 2-3 minutes per side until they have golden-brown grill marks.
Serve the grilled pineapple topped with vanilla ice cream, fresh strawberries, and a mint leaf.