Let pie crusts stand at room temperature for 10 to 15 minutes according to package directions. Unfold pie crusts. Place on ungreased baking sheet.
In a saucepan, cook onion and garlic in butter or margarine until tender. Add catfish; cook and stir about 5 minutes or until fish flakes easily. Use spoon to break fish into small pieces.
Add goat cheese or cream cheese and basil. Cook and stir until cheese melts. Remove from heat.
Spoon half of the catfish mixture onto half of each pie crust. Moisten edges with water. Fold pie crusts in half; turn edges under. Seal edges with the tines of a fork. For smaller pastries, cut pie crusts into thirds.
Prick top of pie crust, and brush with milk. Bake in a 375º F. oven for 25 to 30 minutes or until pastry is brown. Cut into wedges, and serve warm.
Note: Makes 2 pastries or 8 servings.