Preheat oven to 420 degrees F. Line a large baking sheet with parchment paper.
Slice tofu into 1" cubes. In a medium mixing bowl or shallow baking dish, mix together the vegetable broth and soy sauce. Add the sliced tofu cubes, tossing to cover with the marinade. Let marinate for at least 10 minutes.
Remove the tofu from the marinade. Press firmly with a paper towel to remove excess moisture.
Add tofu to a large plastic bag or container. Sprinkle with cooking oil, corn starch, pepper and extra seasonings if using. Gently toss to coat the tofu. You can also move your hands on the outside of the plastic bag to coat the tofu.
Place the tofu in a single layer on the parchment paper-lined baking sheet. The tofu cubes should not be touching each other. Bake in 420 degree oven for 25-30 minutes, or until golden brown. Be careful not to overcook as they will crisp up a little after removing from the oven.
Tofu: Extra firm or super firm tofu are the best options but firm will also work.
Corn starch: Arrowroot starch can be used in place of corn starch as needed.
Oil: Choose canola, vegetable, peanut, or sunflower oil. Olive oil has a low smoke point, so it is best not to use for roasting.
Keeps for 3-4 days in the fridge. To keep crispy when reheating, bake in a 425 degree oven for 5 minutes, or until warmed through.