1. Marinate the chicken: In a large bowl, whisk the eggs with 3 tablespoons of the cornstarch until smooth. Season the chicken on all sides with salt, and submerge it in the egg mixture. Cover with plastic wrap and refrigerate for at least 4 hours and up to 6 hours.
2. Make the lemon sauce: In a medium saucepan, combine the soy sauce, lemon juice, white vinegar, and sugar. Simmer over medium heat until the flavors come together and the sugar has dissolved, 3 to 5 minutes. Add the ginger and garlic, and simmer for 1 additional minute. Remove from the heat and keep the sauce warm.
3. Fry the chicken: Pour the peanut oil into a large heavy-bottomed pot (or wok) and bring it to 350 degrees F over medium-low heat. (Use a deep-frying thermometer to monitor the temperature as it heats.) Remove the chicken from any liquid in the bowl and spread it in an even layer on a baking sheet. Use a fine-mesh sieve to sprinkle the remaining 3 tablespoons cornstarch in an even layer over all sides of the chicken pieces. Drop some of the lemon slices carefully into the oil and fry until light brown with crisped edges, just 1 to 2 minutes. Remove with a slotted spoon to a baking sheet lined with a kitchen towel. In batches, add the chicken to the hot oil and cook until crispy and browned, 3 to 5 minutes. Use a slotted spoon to transfer the chicken to the baking sheet. Season with salt.
4. Finish the dish: Stir the lemon slices and fresh chile into the sauce. Arrange the fried chicken pieces on a platter, and pour the sauce over them. Serve immediately.
"The Home Cook: Recipes to Know by Heart" by Alex Guarnaschelli © Clarkson Potter 2017. Provided courtesy of Alex Guarnaschelli. All rights reserved.