First, prep the tofu by removing it from the package, cutting in half, and pressing it between two towels or paper towels to remove excess moisture. While the tofu is pressing, prep the veggies by chopping the red pepper, green pepper, and garlic.
Once the tofu is pressed, cut it into 1-inch cubes and add it to a bowl. Add in the cornstarch, white pepper, and salt to your liking. Then toss together until the tofu is completely coated in cornstarch.
Add 1 Tablespoon of sesame oil to a wok and turn on the heat. Once the oil is hot, add in the tofu. Cook the tofu on medium/high heat for about 15 minutes until it is crispy on the outside. Once it is done cooking, remove from the wok and set aside.
While the tofu is cooking, make the kung pao sauce. Add the soy sauce, water, black vinegar, brown sugar, dark soy sauce, and cornstarch to a bowl. Whisk together and set aside.
Add the additional 1 Tablespoon of sesame oil to the wok and turn to high heat. Then, add in the chopped green peppers, red peppers, garlic, ground Sichuan peppercorn, and dried red chili peppers. Cook in the oil for about 5 minutes until the peppers are beginning to brown and the garlic is fragrant.
Add the crispy tofu and kung pao sauce to the wok. Cook with the veggies for another 2 minutes until the sauce begins to thicken.
Finish by adding in the chopped scallions and toasted peanuts and cooking everything together for another 1-2 minutes. Then, serve over rice and enjoy!