Once the grill or smoker is up to 250°F and producing smoke, place the pineapple slices into the smoker, or on the cool side of the grill.
Whisk together the brown sugar, maple syrup, and bourbon whiskey. Or use water if you don't want to use bourbon.
¾ Cup Dark Brown Sugar, ¼ Cup Maple Syrup, ¼ Cup Bourbon Whiskey
Every 10 minutes or so, baste the pineapple slices on each side with some of the maple bourbon mixture using a good silicone basting brush.
Flip and rotate the pineapple slices as need for even cooking on the grill or smoker.
After about 45-60 minutes, check whether the outside is carmelizing and if not, turn the heat up to about 350°F or move the pineapple slices over the direct heat of a medium gas burner or lit charcoal.
Watch the pineapple slices carefully at this point and flip as needed just to get some light caramelization and not burn the smoked pineapple.