Steamed Fish with soy sauce

Ingredients:

• 11/2 lbs halibut (cut into 4 pieces)
• 3 green onions (cut into 3 inch lengths)
• 2 fresh mushrooms (sliced)
• 6 leaves napa cabbage (sliced into 4 inch pieces)
• 2 slices fresh ginger root (finely chopped)
• 2 cloves garlic (chopped)
• 1/4 cup low sodium soy sauce
• crushed red pepper flakes (to taste)
• cilantro sprigs (fresh, for garnish)