Seafood Enchiladas

• 1 Tbs. butter
• 1 cup chopped green onions
• 1 cup chopped mushrooms
• 1 lb. white crabmeat
• 1 lb. boiled shrimp, medium size
• 1/2 cup sour cream
• 2 tsp. granulated garlic
• 2 tsp. salt
• 1 tsp. white pepper
• 16 flour tortillas