Sprinkle a generous amount of salt and pepper on a plate.
Place the fish on the plate and turn several times to coat all over; set aside.
Pour 2-inches of oil in a large skillet with high sides.
Over medium-high heat, heat to 350°F.
In a medium bowl, add the turmeric, 1 cup of the flour, salt to taste and enough beer so that the batter is the consistency of thick pancake batter; whisk until smooth.
Place the remaining flour in a baking dish.
Add the fish to the flour and coat all over.
Working with one piece of fish at a time, shake off any excess flour, then add to the batter.
Coat well, allowing any excess batter to drip off.
Add the fish to the oil and fry, flipping about halfway through, until both sides are golden; 4 to 6 minutes total depending on the thickness of your fish.
Adjust the heat as necessary during cooking.
When cooked, transfer the fish to a paper towel-lined plate and season with salt.
Top each bottom bun with slaw, then with a piece of fish and then with more slaw.
Top with the top buns and serve.