2 tbsp. olive oil
1 tbsp. vinegar
1/2 tsp. salt
1/4 tsp. pepper
2 tsp. onions, finely chopped
2 catfish, 1 lb. each
3 tbsp. combined butter & vegetable oil

Remove the slime from the fish with paper towels. Remove the head and backbone without cutting them in half. Preheat the broiler. Use a shallow baking dish large enough to hold the fish flat in a single layer.

Mix in a small bowl the oil, vinegar, salt, pepper and onions; pour over the fish in the baking dish. The fish should have been placed with the skin side down. Let it sit this way for 20 minutes, then turn the fish over and soak in the marinade for another 20 minutes. Brush the broiler rack with the oil-butter mixture and place the catfish, skin side down on the rack about 3 inches from the source of heat for 15 minutes. Grill only on one side, basting from time to time with the melted oil-butter mixture. After the fish has turned golden brown and flaky, serve at once with horseradish butter.