Blackened Redfish

Steps

1. Start with the grits. In a heavy saucepan, bring the milk, 500 ml (2 cups) of the water, and 1 teaspoon of salt to a simmer. Pour in the grits in a slow stream, whisking constantly to prevent lumps. Turn the heat to low, cover three-quarters of the way, and cook for 35 to 45 minutes, stirring every 5 minutes and scraping the bottom well. If they get too thick, add a little of the remaining water, hot. They're ready when the grains are tender to the bite and the texture is a thick porridge that spreads slowly.
2. Meanwhile, in a shallow dish, mix the paprika, 2 teaspoons of salt, the garlic and onion powders, the cayenne, 1/2 teaspoon of black pepper, the white pepper, the thyme, and the oregano. Crumble the herbs between your fingers so the blend is even.
3. Seed the bell peppers and cut them into 1/2-inch (1 cm) strips. Heat the oil in a 12-inch (30 cm) cast-iron skillet over medium-high heat and grill the strips for 6 to 8 minutes, stirring now and then, until soft, blistered, and charred in spots. Season with a pinch of salt, keep warm in a covered bowl, and wipe out the skillet with paper towels.
4. Get the kitchen ready before blackening the fish: range hood on high, windows open, the kitchen door closed to the rest of the house, and a lid within reach to smother any flame. This makes a lot of smoke. If you can, do it outdoors on a grill side burner or a powerful camp stove.
5. Take the fillets out of the fridge 15 minutes ahead and pat them very dry with paper towels. Melt 100 g (7 tablespoons) of the butter in a small saucepan and pour it into a shallow dish. Finish the grits off the heat with the rest of the butter and the rest of the black pepper, taste, cover, and keep warm over the lowest heat.
6. Heat the cast-iron skillet dry over the highest heat for 8 to 10 minutes, until it smokes lightly and a drop of water vanishes instantly, around 500°F (260°C) on an infrared thermometer.
7. Dip a fillet in the melted butter on both sides, then lay it in the spice blend and press so each side gets a thick coating. Set it in the skillet, no more than two at a time, and drizzle 1/2 teaspoon of melted butter over the top, carefully, as it can flare. Leave it alone for 2 minutes, until the underside forms a blackish-brown crust.
8. Flip the fillet with a thin spatula, drizzle another 1/2 teaspoon of melted butter on top, and cook for 1 1/2 to 2 minutes. The fish is done at 130 to 140°F (55 to 60°C) in the thickest part: the flesh is opaque and starts to separate into flakes when pressed. Move it to a warm plate, wipe the skillet with a paper towel held in tongs, let it reheat for 1 minute, and cook the rest of the fillets.
9. Cut the limes into wedges. Spoon the grits into shallow bowls, set a blackened fillet on top, add the grilled red pepper strips alongside, and two lime wedges. Serve right away: the crust softens within minutes from the steam.