How to Make It
In a large nonstick skillet, heat the olive oil. Add the radishes, season with salt and cook over moderately high heat, stirring occasionally, until golden and crisp-tender, about 3 minutes. Transfer to a plate and let cool slightly. Wipe out the skillet.
Season the chicken breasts with salt and pepper. Dredge in the flour; shake off the excess. Heat 2 tablespoons of the oil in the skillet. Add 2 of the chicken breasts; cook over moderately high heat until golden on the bottom, about 3 minutes. Flip the chicken and cook until golden and white throughout, 2 to 3 minutes longer. Transfer to a large plate. Repeat with 2 tablespoons of oil and the remaining chicken. Wipe out the skillet.
Heat the remaining 1 tablespoon of oil in the skillet. Add the garlic and cook over moderate heat, stirring, until fragrant, 30 seconds. Add the wine and cook until almost evaporated, 1 minute. Add the stock and bring to a boil. Whisk in the butter, lemon juice, capers and parsley and cook until slightly thickened, about 2 minutes. Season the sauce with salt. Return the chicken to the skillet, 2 pieces at a time, and turn to evenly coat with the sauce. Transfer the chicken to plates and spoon the remaining sauce on top. Halve the radishes, scatter over the chicken and serve.