Preheat the oven to 425°F (220°C). Line a baking sheet with parchment paper.
To make the cauliflower, combine 1/4 cup cornstarch, water, and salt and pepper together in a medium bowl. Place the panko bread crumbs on a separate plate. Toss the cauliflower florets into the cornstarch mixture and then into the panko breadcrumbs. Place the florets onto the baking sheet.
When all the cauliflower has been coated, place the baking sheet into the hot oven and bake for 30-40 minutes until the cauliflower is tender in the middle when pierced with a fork
Meanwhile, add all the ingredients for the sauce into a small pot and whisk well. Place over a medium heat and bring the sauce to the boil. Now lower the heat and continue to simmer for 5-7 minutes until the sauce thickens.
Remove the baked cauliflower from the oven and place it onto a serving dish. Pour over the orange sauce and garnish with sesame seeds to serve.
Notes
Soy-Free: for soy-free, substitute a soy sauce for a soy-free option such as coconut aminos.