Turtle Creek Sole

2 pounds sole fillets
1/2 cup finely chopped onion
1/4 cup butter, melted
3/4 cup sour cream
2 teaspoons grated lemon rind
1 tablespoon fresh lemon juice
1/2 teaspoon dried whole dillweed
Salt and pepper, to taste

Place fillets in a 13 x 9-inch baking dish; set aside.

Saut