Cut the pineapple into thick spears and preheat a grill over medium high heat (approximately 400 degrees F.). Rub the grill grates with oil so that the pineapple does not stick to the grates.
Mix the melted butter and brown sugar together in a microwave safe bowl. Heat in the microwave for 30-45 seconds. Then whisk together to make sure that the brown sugar is combined into the butter and has a thin consistency.
Grill the pineapple spears for 5-6 minutes (flipping halfway through the cook time) until both sides of the pineapple are browned. Then brush the brown sugar mixture onto the pineapple spears with a basting brush. Cook for 1-2 more minutes per side.
Remove the pineapple from the grill. Serve warm and enjoy!
Notes
Make sure to wait to brush the brown sugar mixture onto the pineapple as it could cause the pineapple to burn if brushed on right when the pineapple is placed on the grill.
Refrigerate the leftovers in an airtight container for up to 2-3 days.