Cut chicken breasts in half. Pound each piece with a meat mallot between sheets of plastic wrap to 1/4" thick. Season cutlets with salt and pepper and dust with flour.
Heat oil over medium heat in saute pan. Saute cutlets until golden on one side, then flip them and cover pan; saute a few minutes more. Transfer cutlets to a plate, cover with foil, and set aside.
SAUCE: Remove saute pan from heat, add garlic and stir into still-warm pan for about a minute. Deglaze pan with wine over medium-high heat until wine is evaporated. Add broth, tomatoes, olives and lemon juice. Bring to a boil and reduce mixture by half. Return chicken to pan and cook another minute per side.
Serve sauce over chicken and top with crumbled feta and parsley.