- Preheat oven to 425ºF. Slice zucchini in half lengthwise and use a spoon to scoop out the seeds down the center. Slice off the end of zucchini if needed to help them fit into pan and lift out easily. Place zucchini in a 9X13 inch oven safe baking pan. Bake zucchini for 15 minutes.
- In the meantime, stir together sesame oil, soy sauce, brown sugar, garlic, ginger, and chili flakes in a small bowl. Set aside. Heat a medium nonstick pan over medium-high heat. Add ground chicken and brown for 8 minutes. Discard any liquid from the pan and return to stove. Stir the sauce into pan with chicken and cook 30 seconds longer, stirring regularly.
- Scoop chicken into zucchini and sprinkle with mozzarella cheese and red onion. Return to oven for ten minutes. Turn the oven to broil and broil for 3 minutes or until cheese is bubbly and golden brown in spots.
- Carefully remove baking pan from oven and cool 5 minutes. Sprinkle with cilantro and sesame seeds before serving.