Mexican-Style Baked Fish

1/3 cup sour cream
1 tablespoon lemon juice
1/2 teaspoon chili powder
1 pound orange roughy or red snapper fillets
1 1/4 cups crushed corn chips
2 tablespoons butter or margarine, melted
Avocado slices (optional)
Tomato slices (optional)

Combine sour cream, lemon juice and chili powder. Dip fillets in this mixture and dredge in corn chips, coating well. Place fillets in a lightly greased 13 x 9-inch baking dish. Drizzle with butter. Bake at 450 degrees F for 12 to 15 minutes or until fish flakes easily when tested with a fork. If desired, serve with avocado and tomato slices.