02Meanwhile, melt remaining 1 tablespoon butter with remaining 1 tablespoon oil in heavy medium skillet over medium-high heat. Add radishes; sprinkle with coarse salt and pepper; cook without stirring until radishes begin to brown, about 4 minutes. Continue to cook radishes until crisp-tender, stirring occasionally, 5 to 7 minutes longer.
03Cut chicken breast halves crosswise into 1/2-inch-thick slices; arrange on platter. Place radishes around and over chicken. Spoon sauce over chicken and radishes. Garnish with tarragon sprigs and serve.