Make the flour coating: In a large bowl, combine the flour and baking powder. Slowly add the cold water and whisk to combine. Start with about 1.5 cups and add more if needed. Break up any clumps of flour so that the mixture is smooth. What you want to get is a thick and moist flour mixture that will cling to the chicken. Please see reference photo on the post.
Heat a large frying pan or Dutch oven. Fill the pan or Dutch oven with oil about 1-inch deep. Heat the oil to 350-375°F.
Cooking in small batches, fry the chicken on both sides until crispy and cooked through, about 10-15 minutes. Don't crowd the chicken.