Press the tofu for at least 15 minutes to remove excess water. You can do this by using a tofu press or by making a DIY tofu press. To do so, simply wrap the block of tofu in paper towels or clean dishcloths and place it in a shallow bowl. Then, stack heavy items on top to drain the excess water.
Cube the tofu and toss in a large bowl. Coat in the tamari and toss until evenly coated. Sprinkle in the cornstarch, garlic powder, onion powder, black pepper and a pinch of salt and toss carefully to coat.
Heat a large pan on medium-high heat and coat the base of the pan in vegetable oil. Add the tofu to the pan in batches and pan-fry on each side until crispy and golden brown, 2-3 minutes each side. Don't overcrowd the pan. Drain on wire rack. See above for more tips on frying tofu.
In a large pan, whisk together the sauce ingredients including the cornstarch until well incorporated. Bring the sauce to a soft boil and then reduce to a simmer on medium heat. Simmer until the sauce has thickened. Whisking often.
Add the crispy tofu and toss in the sauce to coat. Allow the tofu to simmer in the sauce for a minute or two more until the sauce has reached your desired thickness.
Serve over rice and top with green onions, orange slices, and sesame seeds. Enjoy!