Preheat oven to 450F
Toss the chopped cauliflower with coconut oil and then lay in a flat layer on a cookie sheet.
Roast for 10-12 minutes, turning once, until slightly golden.
Meanwhile, combine the soy sauce, rice wine vinegar, sesame oil, ginger paste, crushed red pepper, and garlic in a large saucepan. Place over medium heat and cook until simmering, stirring often.
Combine the water and cornstarch to form a slurry, then mix into the soy sauce mixture.
Continue cooking the sauce until it becomes sticky.
Toss the cauliflower in the sauce and then return to the oven for 3-5 minutes.
Garnish with sesame seeds and chopped green onions.