This is the traditional way to blacken fish in a heavy cast-iron skillet. The advantage of doing it outdoors on the grill is that you won't fill the kitchen with smoke.
INGREDIENTS:
1 1/2 cups unsalted butter, melted
6 firm fish fillets (about 1/2" to 3/4" thick)
3 tablespoons Cajun Blackening Spices
PREPARATION:
Preheat grill with heavy cast-iron skillet or griddle in the grill. Get it good and hot. Reserve 12 tablespoons of melted butter for serving and pour the rest into a shallow dish. Dip each fillet into butter and sprinkle cajun blackening spices on both sides.
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Place in skillet. Cook about 2 minutes or until the bottom is almost black but not burned. Flip over. Pour about a teaspoon of butter on the cooked side and continue cooking about 2 minutes or until fillet is finished. Serve immediately with 2 tablespoons of butter for dipping. It's best to cook about 2 fillets at a time. Wipe clean the skillet between each batch of fillets and keep the temperature hot.