Cut tofu: Cut the tofu into cubes, or tear into bite-sized pieces.
Coat tofu with starch: In a mixing bowl, whisk together cornstarch, salt and pepper. Add in the tofu pieces and toss to thoroughly coat. Let the tofu sit in the cornstarch mixture while you heat your vegetable oil.
Heat oil: In a heavy-bottomed skillet or cast iron pan, heat at least 1" of oil to 400°F. (I highly recommend using a thermometer to ensure the oil is hot enough! If it's not, your tofu will take longer to fry and may not get as crispy. It will also retain more oil.) We want to fry the tofu around 350-375°F, but the oil temperature will drop once we add the tofu.
Frying prep: While the oil heats, prepare a baking with a wire rack (my preference), or a paper towel-lined plate to place the tofu after frying.
Add tofu to oil: Add the tofu to the oil — be extremely careful of splattering as you do this! I like to load the tofu pieces into a metal spider and gently shake them into the oil to reduce splashing. Once all the pieces are added, give them a quick stir, and then let them cook undisturbed for 1-2 minutes.
Fry till crispy: The starch should be forming a crust by this point. If any pieces are sticking together, carefully pull them apart with two forks or tongs. Continue to monitor the oil if you have a thermometer and keep it around 375°F. Fry for another 4-6 minutes, until crispy and slightly golden brown.
Enjoy: Transfer the fried tofu to your prepared wire rack or paper towel-lined plate. Sprinkle with extra salt while it's still hot. Check out the notes for some of my recommendations as to how to enjoy fried tofu! Enjoy.