Using a large, flat storage container, whisk together the BBQ sauce, soy sauce, smoked paprika, garlic powder and hot chili powder.
Cut the extra firm tofu into 6 or 7 equal slices. Gently poke holes into the tofu using a fork. Be careful not to put the fork all the way through. (If the holes are too deep the tofu could fall apart.)
Place the tofu into the marinade, and flip tofu to cover both sides in the sauce. Close using the container lid, and allow to marinate for at least 1 hour in the fridge. (Do not marinate for more than 24 hours or the tofu can start to soften)
Preheat the grill to medium-high heat (375 to 450 degrees Fahrenheit).
Lightly grease the grill grates to avoid sticking. Place the tofu onto the grill and cook for 3-4 minutes per side or until char marks appear and the tofu releases from the grates.
Remove from the grill, and brush with the remaining BBQ sauce marinade. Serve and enjoy!