Cut 1 lb extra firm tofu into half inch to 1-inch-thick planks.* Place the planks on a clean kitchen towel on a cutting board.
Place another clean kitchen towel on top and press the tofu gently with the weight of a couple cookbooks. You can also use a tofu press or a heavy cast iron skillet. Press for 30 minutes, minimum.
Once the tofu has been pressed (you’ll see how much water comes out when you feel how damp your clean kitchen towels are!) cut it into cubes.
Add cubed pressed tofu, olive oil, soy sauce, salt, and pepper to a medium mixing bowl and toss until each piece of tofu is covered in the seasoning.
Sprinkle cornstarch over the top of the tofu and gently toss until each piece is evenly coated. I like to use a rubber spatula for this because the tofu is pretty fragile and I want the cubes to stay mostly intact.
Transfer the tofu to a parchment-lined baking sheet. Make sure the tofu pieces have plenty of space between them, this helps them crisp up evenly and keeps them from getting soggy.
Bake for 30 minutes, tossing the tofu and flipping it halfway through.
*The thickness of your tofu should stay in the half inch to full inch range for this recipe; if you go smaller than that, it will dry out too much. If you cut your tofu smaller, just check it sooner in the oven and pull it once it’s nice and crispy and golden brown. For smaller pieces, I recommend baking for around 20 minutes.