Mix the flour, salt and pepper in a separate bowl. In another bowl beat the egg and 1/2 tbsp water together. Place breadcrumbs in another bowl to dredge chicken.
2Dip each chicken breast, first in the flour, then the egg mixture and the breadcrumbs.
Cook each chicken breast in oil over medium heat for about 2 minutes on each side or until browned. Place them on a sheet pan and bake for 10 minutes while you make the sauce.
3For the sauce. In the same pan you cooked the chicken in, wipe it out with a paper towel, melt 2 tbsp butter on medium heat, add the minced garlic, onion, saute until transparent, add wine, capers and lemon juice. Salt and pepper to your taste (capers tend to be salty). Boil over high heat until sauce is reduced to half the amount, swirl in the remainder of the butter to combine. Remove from heat.
4Remove chicken from oven and place in saucepan to cover with juice. Place on plate and spoon lemon sauce over chicken and serve.