Press the tofu: Wrap tofu block in a clean towel and place something heavy on top, like a cast iron skillet. Let sit for 15 minutes to press out moisture. Cut pressed tofu into 1-inch cubes.
Coat the tofu: In a large bowl, toss tofu cubes with cornstarch, salt, and pepper until evenly coated.
Pan fry the tofu: Heat 2 tablespoons vegetable oil in a large skillet over medium-high heat. Add tofu cubes in a single layer and fry for 3-4 minutes per side, until lightly browned. Transfer to a paper towel-lined plate.
Make the sauce: In a small bowl, whisk together the gochujang, soy sauce, rice vinegar, sesame oil, garlic, ginger, brown sugar, cornstarch, and water.
Cook the sauce: Heat remaining 1 tablespoon vegetable oil in the same skillet over medium heat. Add sauce and cook for 2-3 minutes, until thickened.
Add the tofu: Return crispy fried tofu cubes to the skillet and gently toss to coat in the sauce.
Serve: Place rice in bowls and top with gochujang tofu. Garnish with green onions and sesame seeds. Enjoy!
