Slice tofu into inch thick slices and place in a plastic tupperware or container.
In a small bowl, mix together the original and spicy sauces and pour over the sliced tofu. Refrigerate overnight, or for at least 2 hours.
TO GRILL: Heat grill as per model. Once hot, lightly coat with cooking spray/oil/butter and place marinated tofu and cook each side for 3 minutes, until crispy on the outside. Flip and continue cooking until golden brown. TO BAKE: Preheat the oven to 350 degrees. While heating up, coat a large baking tray with oil/cooking spray and place marinated tofu in a single layer. Once hot, bake for 40 minutes, flipping halfway through. TO SEAR: Coat a large pan with cooking spray/oil/butter and heat. Once hot, reduce to medium and place marinated tofu in a single layer. Cook for 3-5 minutes, until golden brown on the edges before flipping and cooking for a further 2-3 minutes. Remove from the heat and serve immediately.