In a large bowl, combine 1 cup of flour, baking powder, salt, pepper, garlic powder, and paprika if using. Whisk thoroughly to distribute all ingredients evenly.

Gradually add milk and water to the dry mixture, whisking constantly to prevent lumps from forming. The batter should be smooth and have a consistency similar to pancake batter—not too thick, not too thin.

Place the remaining cup of flour in a shallow dish for dredging.

Pat the fish fillets dry with paper towels. This helps the batter adhere better and prevents splattering during frying.

Heat vegetable oil in a deep skillet or Dutch oven to 375°F (190°C). You'll need enough oil to submerge the fish halfway.

Dredge each fish fillet in the plain flour, shaking off any excess.

Dip the floured fillets into the prepared batter, allowing any excess to drip off.

Carefully lower the battered fish into the hot oil and fry until golden brown, about 3-4 minutes per side depending on thickness.

Transfer the fried fish to a wire rack set over paper towels to drain excess oil while maintaining crispness.

Serve immediately with lemon wedges for a bright, fresh flavor contrast.