Wrap the tofu in kitchen paper to remove any excess water. Leave for a couple of minutes, change the paper to a dry one, and repeat.
Cut the tofu into medium-sized cubes and place them in a large mixing bowl.
Coat the tofu with the five-spice powder and corn flour. Mix well until all the pieces are equally coated.
Using a frying pan or a wok, heat vegetable oil over medium-high heat and add the coated tofu pieces in batches so you don't overcrowd the pan or wok. When the tofu is evenly cooked and golden brown, remove it from the pan using a slotted spoon and place it on kitchen paper to remove any excess oil. Reserve.
Heat some vegetable oil in a pan over medium heat and finely chopped or pressed garlic and ginger. After cooking for 1-2 minutes, add the turmeric powder and cook for 2 more minutes.
Add freshly squeezed orange juice, vegetable stock or water, orange zest, soy sauce, rice vinegar, and brown sugar. Bring to a simmer and leave simmering for 4-5 minutes.
Dilute the cornstarch in lukewarm water. Add the cornstarch slurry to the simmering sauce and mix well until it thickens. Cook for 5 more minutes and turn the heat off.
Add the cooked tofu and sesame oil into the orange sauce. Combine well, and your orange tofu will be ready to serve.
Garnish with finely sliced scallions, sesame seeds, and orange slices.