Prep the tofu. Press and pat the tofu completely dry. Break it into rough 1-inch nuggets with your hands - the uneven edges help the batter cling and crisp up better. (If using Trader Joe's High Protein Tofu, no pressing needed.)
Make the batter. In a large mixing bowl, whisk together the flour, cornstarch, garlic powder, and salt. Add water gradually and whisk until a slightly runny batter forms - similar to pancake batter consistency.
Coat the tofu. Add the tofu pieces to the batter and toss until each piece is fully and evenly coated.
Fry the tofu. Heat the oil in a large skillet over medium-high heat. Once hot, add the tofu pieces one at a time - do not crowd the pan. Fry for 5–6 minutes per side until deeply golden brown and crispy. Transfer to a plate lined with paper towels.
Make the sauce. Whisk all sauce ingredients together in a bowl until fully combined. Pour into a clean skillet over medium heat and simmer for 5 minutes, stirring frequently, until the sauce thickens and turns glossy.
Combine. Add the crispy tofu to the sauce and toss until every piece is evenly coated.
Serve. Serve immediately over steamed rice and top with sliced green onions. Enjoy!