Start by slicing the chicken breast lengthwise into thinner pieces. Use a meat mallet to gently pound each piece until it's even in thickness. In a shallow dish, mix flour with the zest of half a lemon. Lightly dredge the chicken in this seasoned flour, making sure to coat both sides, then shake off the excess.
In another shallow bowl, beat the eggs well. Add freshly grated Parmigiano Reggiano, a pinch of salt, pepper, and the chopped parsley. This mix adds flavor and helps form the crispy coating. Drench each floured chicken piece into the egg mixture and set aside on a plate.
Heat olive oil in a large sauté pan over medium heat. When hot, add the chicken pieces but don’t overcrowd the pan. Cook each side until golden brown – about 2-3 minutes per side. Transfer them to a plate once browned, and repeat until all pieces are cooked.
In the same pan, lower the heat and add butter along with the reserved tablespoon of flour and garlic cloves. Stir and let it form a light roux. Pour in the white wine and allow it to simmer for a minute or two to cook off the alcohol. Then, add the chicken stock and lemon juice. Stir well until slightly thickened.
Return the browned chicken to the pan, layering the pieces in the sauce. Let them cook for 5–6 more minutes, allowing the sauce to reduce and coat the chicken well. The chicken will finish cooking and become infused with lemony, garlicky goodness.
Top with extra chopped parsley and a few lemon slices for a fresh finish. Serve immediately while warm with your favorite side.