Mince the garlic and then add it to a bowl with all the other marinade ingredients.
Cut the tofu into approximately 1¼-inch cubes, add them to the bowl with the marinade, and mix gently so that the tofu doesn't break. Let the tofu marinate for 2 hours.
Peel the pineapple, remove the core, and cut it into approximately 1¼-inch cubes. If using canned pineapple, drain it and set the juice aside.
Wash the bell peppers, remove the seeds, and cut them into approximately 1¼-inch pieces.
Thread the bell peppers, pineapple, and tofu alternately onto the skewers. Set aside the remaining marinade for basting.
Preheat the grill to medium heat and grill the skewers in a grill pan for 5-8 minutes, turning them carefully several times and basting them repeatedly with the marinade. Once tender and smokey they are ready, enjoy!