Couple of notes:
When cutting the cod, cut against the grain. It will hold together better when cooking. Try and cut your fish in as similar a size as possible. If part of your fillet is thinner try and cook those pieces together and adjust the cooking time slightly.
I used a little more than a teaspoon of lemon zest to balance some old bay that I threw into the batter, in place of the cayenne pepper.
If you decide to cut the recipe in half I would still make a full recipe of batter.
The most important thing to remember is to let your oil get hot enough gradually! It took about 20 minutes on an electric stove to get the oil up to temperature. If you don't have a thermometer to gauge the temp then plop a tiny drop of the batter into the oil when you think it is ready. If it sizzles and bubbles up you are good to go.
Cook your fish in batches. I used a 12" cast iron skillet (thanks mom!). I did 4-5 pieces at a time - don't crowd the pan. Room is one of the keys to the fish getting a nice crispy shell.
Place the finished pieces on a baking towel lined with paper towel and keep warm in a 200 degree oven for up to 20 minutes.
Parker's Fish and Chips (Barefoot Contessa Family Style)
3 pounds fresh cod fillets (try and get as even a thickness as possible)
Freshly ground black pepper
1 cup plus 2 tablespoons all-purpose flour
1 tablespoon baking powder
1 teaspoon freshly grated lemon zest (one small lemon)
1/4 teaspoon cayenne pepper (as noted above I replaced this with Old Bay)
1 cup water
2 extra-large egg
Vegetable oil, for frying
Lay the cod fillets on a cutting board. Pat dry and sprinkle both sides with salt and pepper. Cut the fillets in 1-1/2 by 3-inch pieces.
In a bowl, combine the flour, baking powder, lemon zest, cayenne pepper, 1-1/2 teaspoons salt, and 3/4 teaspoon pepper. Whisk in 1 cup of water and then the eggs.
Pour 1/2-inch of oil into a large frying pan and heat it to about 360 degrees. Dip each fillet into the batter, allowing the excess to drip back into the bowl. Place it very carefully into the hot oil. Don't crowd the pieces. Cook the fish on each side for 2 to 3 minutes, until lightly browned and cooked through - thinner pieces closer to 2 minutes, thicker pieces slightly longer. Remove to a plate lined with a paper towel. Sprinkle with salt.
4 tablespoons good olive oil
1-1/2 teaspoons kosher salt
3/4 teaspoon freshly ground black pepper
1 teaspoon minced fresh garlic (about 2 small cloves)
1 teaspoon minced fresh rosemary leaves
Preheat the oven to 400 degrees F.Scrub the potatoes, cut them in half lengthwise, then cut each half in thirds lengthwise. You'll have 6 long wedges from each potato. Place the potatoes on a sheet pan with the olive oil, salt, pepper, garlic, and rosemary. With clean hands, toss all the ingredients together, making sure the potatoes are covered with oil. Spread the potatoes in a single layer with 1 cut side down.
Bake the potatoes for 30 to 35 minutes, turning to the other cut side after 15-20 minutes. Bake until they are lightly browned, crisp outside, and tender inside. Sprinkle with salt and serve immediately.