1. Preheat the oven to 375°F; lightly oil a baking pan.
2. Rinse the fish and place it in a shallow dish.
3. Pour the buttermilk over the fillets.
4. In a separate shallow dish, combine the pecans, bread crumbs, garlic, parsley, thyme, paprika, salt, and cayenne.
5. One at a time, remove the fillets from the buttermilk, allowing the excess to drain off, and then dredge in the pecan mixture to coat all sides. Place each coated fillet in the baking pan.
6. Bake for 30 to 45 minutes, depending upon the thickness of the fillets, until the topping is lightly browned and the fish is tender and flakes easily with a fork.