1/2 cup dark rum
1/2 cup packed brown sugar
1 tsp. ground cinnamon (plus extra for dusting)
1 pineapple, cored and cut into about 6-8 rings (choose desired thickness)
favorite vanilla ice cream
In a small bowl, mix together rum, brown sugar, and cinnamon. Then in a glass baking dish (or other container), lay out the pineapple rings and pour the rum mixture over them. Toss to coat, then let soak for at least 15 minutes, flipping the pineapple midway through.
When you are ready to cook the pineapple, strain out the extra rum sauce from the pan of pineapple, and transfer it to a small saucepan. Bring the sauce to a simmer over medium-high heat, then reduce heat to medium-low and simmer for about 6-8 minutes, or until reduced by half. Set aside.
While the sauce is cooking, clean the grill grates with oil and heat the grill (grill pan or sauce pan indoors is fine) to medium-high heat until hot. Add pineapple slices in an even layer (you may need to do this in multiple batches if doing indoors) and cook for 1-2 minutes per side until browned and grill marks appear. Transfer to a serving plates, and set aside.
Top each pineapple ring with a scoop of ice cream and drizzle with rum sauce. (If desired, you can also lightly dust the pineapple with some extra cinnamon.) Serve immediately.