Shrimp and Crab Étouffée

Ingredients

• 1⁄4 lb. butter
• 1 cup onion, finely chopped
• 1⁄2 cup green bell pepper, finely chopped
• 1⁄2 cup celery, finely chopped
• 1 tbsp. garlic, peeled and minced
• 1 tsp. salt
• 1⁄2 tsp. cayenne
• 2 lb. medium shrimp, peeled and deveined
• 2 cups hot Double-Rich Fish Stock
• 2 tbsp. cornstarch
• 1 lb. lump crabmeat
• 1⁄4 cup scallions, finely chopped, for garnish
• 1⁄4 cup parsley, finely chopped, for garnish