Gather all ingredients. Preheat an outdoor grill for high heat.

Coat one side of a large piece of aluminum foil with cooking spray. Place beets and butter on foil; season with salt and pepper.

Wrap foil over beets. Place packet on the grill grate. Cook until beets are very tender, about 30 minutes.

Allow beets to cool before serving, about 5 minutes. You don't even need to peel to enjoy!