Preheat oven to 400 degrees F.
Pound out chicken breast to about 1/4-inch. Combine equal amounts of spinach, ham and Swiss cheese and form a ball about the size of a grapefruit. Carefully wrap the flattened chicken breast around the ball mixture and put on sheet tray. Freeze rolundo until solid.
Once frozen, roll in flour, shaking off excess. Beat egg in a shallow dish and dredge chicken, shaking off excess. Coat with seasoned bread crumbs and refreeze. When needed, remove from freezer and let rolundo thaw slightly. Once softened, cut into 1-inch medallions, top off with butter and bake for about 15 minutes or until chicken is thoroughly cooked.