Russian cuisine
The main difference between the old time "côtelette de volaille" and the modern chicken cutlet Kiev-style is that the elaborate stuffings of the former are replaced by butter. The use of butter for chicken cutlets has been known in Russian cuisine at least since the invention of the Pozharsky cutlet in the first half of the 19th century. The Pozharsky cutlets are breaded ground chicken patties for which butter is added to minced meat. This results in an especially juicy and tender consistency. The dish was a widely appraised invention of 19th-century Russian cuisine, which was also adopted by French "haute cuisine" and subsequently by the international cuisine.