Wash the cauliflower thoroughly and cut it into evenly sized bite-sized florets.
In a medium bowl, whisk together the flour, cornstarch, baking powder, salt, and water until the batter is smooth and free of lumps.
In another bowl, combine the breadcrumbs and desiccated coconut.
Dip each cauliflower floret into the batter, allowing any excess to drip off.
Coat each battered floret evenly in the breadcrumb mixture until completely covered.
Heat several inches of neutral oil in a deep skillet or heavy pot over medium-high heat.
Fry the coated florets in batches for 5 to 7 minutes until they are golden brown and crispy. Transfer them to a wire rack instead of paper towels to help maintain their crisp texture.
In a separate bowl, whisk together the orange juice, orange zest, maple syrup, soy sauce, rice vinegar, 2 tablespoons water, cornstarch, and the remaining 4 tablespoons water until smooth.
Pour the glaze into a saucepan and cook over medium heat, stirring constantly until it thickens into a glossy sauce.
Add the crispy cauliflower to the pan and gently toss until every piece is evenly coated with the sauce. This Vegan Orange Cauliflower is best served immediately for maximum crispiness.
Garnish with fresh orange slices and sesame seeds before serving over steamed rice.