Perfect Batter for Fish

I received this recipe from Martin James:

• Ready In: 53 mins
• Serves: 4

Ingredients

• 1 1⁄2 lbs  fresh  halibut or 1 1⁄2 lbs  sole
• 3  teaspoons lemon juice
• 1  cup cold water
• 1⁄4 teaspoon salt
• 1⁄4 teaspoon white pepper

• COATING FOR FISH

• 1⁄2 cup all-purpose flour
• 1⁄4 teaspoon salt
• 1⁄4 teaspoon white pepper

• BATTER

• 1⁄2 cup  luke water
• 1 1⁄2 teaspoons active dry yeast
• 3⁄4 cup all-purpose flour or 3⁄4 cup potato flour
• 1⁄4 teaspoon salt
• 1  teaspoon olive oil or 1  teaspoon canola oil
• 3⁄4 cup beer, of your choice
• 1  large  egg white
• 1  pinch granulated sugar

Directions

1. TO PREPARE FISH:
2. In a bowl, mix together lemon juice and cold water.
3. Remove skin from fish and discard.
4. Cut fish into desired size.
5. Place fish in lemon/water and wash well.
6. Remove from water and season with salt and pepper.
7. Place in refrigerator to chill while preparing batter.
8. TO PREPARE BATTER:
9. In a small bowl, add luke warm water and sprinkle yeast over.
10. Cover and let stand for 10 to 15 minutes until dissolved and frothy.
11. In a medium size mixing bowl, mix together flour, salt and sugar.
12. Make a well in the center.
13. Add dissolved yeast, oil and 2/3's of the beer.
14. Stir with a wooden spoon to combine.
15. Now stir in the remainder of beer and mix well.
16. Let batter stand, coverred, in a warm place for 30 to 35 minutes until it has thickened and becomes frothy.
17. Prepare deep fryer using a vegetable oil; heat to 375 degrees F.
18. In a small bowl, whip egg white until soft peaks form.
19. Fold egg white into refrigerated batter.
20. In a bowl, mix together 1/2 cup flour, 1/4 teaspoon salt and 1/4 teaspoon of white pepper.
21. Dry fish on paper towelling.
22. Coat fish in seasoned flour patting the fish so that it is evenly coated.
23. Shake off any excess flour.
24. Using a fork, dip coated fish in batter and let excess batter drip off.
25. Carefully lower one or two pieces of fish into hot oil and deep fry for about 2 minutes until crisp and golden brown; turning fish once. Continue cooking the remaining fish pieces.
26. Serve with a tartar sauce.