How to Make It
Using a sharp knife, thinly slice each chicken breast half on the diagonal 1/2 inch thick. Pound the chicken slices between sheets of wax paper until they are 1/4 inch thick.
Heat 2 tablespoons of the oil in a large skillet. Add half of the chicken and cook over high heat until barely done, about 1 minute per side; it will still be opaque in places. Transfer the chicken to a plate and repeat with the rest, adding more oil to the pan as necessary.
Add any remaining oil to the skillet, along with the wine and lemon juice. Season with salt and pepper and bring to a boil over high heat. Return the chicken to the skillet and cook, stirring constantly, until the slices are white throughout, 2 to 3 minutes.
Line a platter with the watercress and radicchio and arrange the chicken slices on top. Garnish with the lemon slices and serve immediately.