Chicken-Stuffed Mushrooms

1/4 cup chopped onion (about 1 small, 2 tablespoons chopped fresh coriander, 1 egg lightly beaten, 1 tablespoon Dijon mustard, 1 1/2 teaspoons finely chopped ginger, 2 teaspoons soy sauce, 1 clove garlic -finely chopped, 250g minced chicken, 12 large mushrooms - stems removed.
Heat oven to 230 C. Spray cookie sheet with nonstick cooking spray. Mix all ingredients except mushrooms. Fill mushroom caps with chicken mixture. Place mushrooms, filled sides up, on cookie sheet. Bake 7 to 10 minutes or until tops are light brown and chicken mixture is done. Serve hot.