Start by cutting the chicken breasts into bite-sized pieces. This allows for even cooking and helps the batter adhere better. Toss the chicken in olive oil, sea salt, and black pepper. Make sure every piece is coated evenly.
In one bowl, beat the eggs. In a second bowl, mix the cornstarch and all-purpose flour together. Dip each piece of the coated chicken into the egg first, then dredge it in the flour mixture. This double coating will give it that crispy texture we’re after.
Heat oil in a large skillet over medium-high heat. Once hot, carefully place the battered chicken pieces in the skillet. Avoid overcrowding, as you want the chicken to fry evenly. Fry in batches if needed. Cook the chicken for about 3-4 minutes on each side until golden brown. Remove and drain on paper towels.
In the same skillet, melt the butter over medium heat. Add the lemon juice, sugar, chicken broth, and salt. Bring this mixture to a gentle simmer. Stir occasionally to ensure the sugar dissolves completely.
Once the sauce has simmered for a few minutes, stir in the cornstarch slurry. This will thicken the sauce nicely. Continue cooking for another 2 minutes until it reaches a beautiful viscosity.
Add the crispy chicken back into the skillet, ensuring it's coated in the sauce. Toss everything to mix well, then sprinkle the green onions and parsley over the top. Serve the Lemon Chicken with lemon wedges on the side.