Pound chicken to 1/4-inch thickness.  Season the inside with salt, pepper and tarragon.  Place cheese in the center and fold chicken around it. Roll in flour; dip in egg, then roll in crumbs.  Place chicken, seam side down, on a plate refrigerate for 30 minutes.  In a skillet, saute chicken in butter and oil until golden.  Place in a small shallow baking dish.  Bake, uncovered, at 375 degrees for 15 minutes or until juices run clear.