Fire up the grill, prepare it for direct grilling. When the flames have died down and you have a nice bed of glowing embers, it's time to start grilling.
Place the pineapple on the grill grates above the charcoal.
Rotate the pineapple a little bit every 3-5 minutes, a little bit a time, for a total of 5-6 rotations. It should become almost all black.
When the pineapple is done, remove it and start with the mop sauce.
Pour bourbon and sugar in a pan and heat it up on the grill so the sugar dissolves.
Peel the pineapple with a knife and cut it in slices.
Place a griddle or cast iron pan on the grill and let it get hot. Now place the pineapple slices on the griddle and start searing.
Sear the slices 1-2 minutes per side, and then flip. After each flip you spoon the bourbon sauce on the slices.
Keep flipping and searing and mopping 3-4 times until the color looks nice.
Serve the slices in a bowl with some vanilla ice cream. If there's leftover mop sauce now is a good time to spoon the rest over the pineapple in the bowls.