Add enough oil to a heavy-medium pot to reach a depth of 3 inches. Heat the oil over medium heat until it is hot but not smoking (350 degrees on a candy thermometer). As you fry, adjust the heat to maintain the temperature.
Working in batches, carefully slip the frozen French fries into the hot oil. Fry until pale golden but still limp, about 2 minutes. Transfer the fries with a slotted spatula to a wire rack set over paper towels to drain. When they all have been fried, fry them for a second time in batches, starting with the first batch fried, until deep golden and crisp, about 2 to 3 minutes. Transfer the fries to the rack to the drain. Season with salt.
Pour the milk into a shallow pan. Add the fish to the milk, turning the pieces until they are drenched. Sift the flour, baking powder, and salt together onto a platter, then dredge the pieces of fish in the flour, making sure to coat all sides.
Increase the heat slightly so the oil temperature reaches 360 degrees. Working in batches, carefully slip the fish into the hot oil. Fry until golden brown, about 5 minutes, turning the fish over halfway through. Transfer fish with a slotted spatula to the rack. Season with salt. Serve hot with tartar sauce, the wedges of lemon and the french fries.
– See more at: http://www.saucemagazine.com/blog/?p=30264#sthash.oylvFelZ.dpuf
One 2-pound bag frozen french fries
Salt
1½ cups milk
2 pounds cod filet, cut into 8 equal pieces
1½ cups all-purpose flower
1½ tsp. baking powder
1 tsp. salt
Tartar sauce
1 lemon cut into wedges
This article appears in June 2013.