Wrap tofu (12-16 ounce block) in a clean kitchen towel, gently squeeze any extra water and pat dry. If your tofu is softer, it would benefit from being pressed. (see notes).
Preheat oven to 400º F.
Cut or break the tofu into ~1" pieces. Place in a large mixing bowl. Sprinkle the soy sauce, sambal, garlic powder, black pepper, and oil over the tofu and toss to coat using a large spoon or your hands.
Sprinkle 1 tablespoon cornstarch over the tofu and shake again to coat the tofu. If the tofu is still wet/juicy, add another 1 tablespoon cornstarch and mix until the tofu is coated and sticky (see photos). No dry spots.
Cover a baking sheet with parchment or a silicone mat, add 1 tablespoon of olive oil and spread evenly over the surface. Arrange tofu on the baking sheet in a single layer with space between. *The oil is optional.
Bake at 400º F for 12 minutes. Flip the tofu pieces over and return to the oven for an additional 6 minutes. Bake for additional time for a more well done tofu texture.