Peel the potatoes and cut them into thick fries.

Soak the cut fries in cold water for at least 30 minutes to remove excess starch.

Heat vegetable oil in a deep fryer or heavy-bottomed pot to 350°F (175°C).

In a large mixing bowl, whisk together flour, baking powder, salt, and pepper, then gradually whisk in cold sparkling water until the batter is smooth.

Drain the soaked fries and carefully fry them in the hot oil for 5-7 minutes until golden and crispy, then remove with a slotted spatula and drain on paper towels. Season with salt.

Dip each fish fillet into the batter, gently lower into the hot oil, and fry for about 5 minutes or until the batter is golden and the fish is cooked through.

Remove the fried fish with a slotted spatula and drain on paper towels to maintain crispiness.

Optional: For extra crispy chips, let them cool for a few minutes after the first fry then return them to the hot oil for an additional 2-3 minutes.