Combine Blackening Seasoning ingredients in a bowl and mix well. Rub fish with olive oil and then coat evenly with spice mixture. Cover and refrigerate for 30 – 60 minutes. Heat bacon grease in a heavy skillet, preferably cast iron, over high heat. Add fish and sear on one side until blackened. Flip over and sear other side, but only until fish is just cooked and not overcooked.