Thaw fish, if frozen. If using fillets, separate fillets, or cut fillets or steaks into 4 serving-size portions. Rinse and pat dry with paper towels. Measure thickness of fish. (To measure thickness of fish fillets or steaks, place a ruler against the thickness part of the fish. Use this measurement to calculate the cooking time for fish. Generally allow 4 to 6 minutes for each 1/2 inch thickness of fish.)
Pour buttermilk into a shallow dish. In another shallow dish combine bread crumbs, parsley, dry mustard, salt, and pepper. Dip fish into buttermilk. Then roll fish in crumb mixture. Place coated fish in a greased shallow baking pan.
Sprinkle fish with coarsely chopped almonds. Drizzle melted butter or margarine over fish. Bake in a 500 degree F oven until golden and fish flakes easily with a fork. Allow 4 to 6 minutes for each 1/2 inch of thickness.
To serve, transfer fish to a warm serving platter; garnish with cucumber slices, endive, and ripe olives, if desired. Serve with lemon wedges, if desired. Makes 4 servings.