If using an oven, preheat it to 350 degrees Fahrenheit (175 degrees Celsius; gas mark 4). If using an air fryer, preheat it to 250 degrees Fahrenheit (120 degrees Celsius). Pat the tofu dry thoroughly with paper towels. Place the pieces on a baking sheet (or the tray of the air fryer) without overlapping.

In a small bowl, combine the light and dark soy sauces, liquid smoke, five-spice powder, sugar, and tea powder for the sauce and stir to mix well. Carefully spoon half of the sauce over the tofu. Use the back of the spoon to spread the sauce to cover the entire top of the tofu, without too much pooling on the baking sheet.

If using an oven, bake for 20 minutes. Remove the baking sheet from the oven. Flip over the tofu and spoon the rest of the sauce on top. Bake for another 20 minutes, until the sauce is fully absorbed. You can serve the tofu now or, if you prefer a firmer texture, you can flip over the tofu again and bake for another 10 to 20 minutes.

If using an air fryer, cook for five minutes. Flip over the tofu and spoon the rest of the sauce on top. Cook for another five minutes, until the sauce is fully absorbed. You can serve the tofu now or, if you prefer a firmer texture, you can flip over the tofu again and bake for another five minutes.