Attention! Get an assistant chef to make the garnish, so your ready cutlets don't sit there waiting and get cool in the meantime.
Leave the butter at room temperature to soften. Cut the dill and lightly salt it, add it to the butter and form all this into a small sausage with a diameter of about 1. Wrap in foil and put in the freezer to freeze (about 10 min.).
In the meantime, prepare the fillets. It is best to cut them from the chicken yourself and not buy them ready, because you will get that bone that master chefs place a decoration on that looks like a paper toy for a Christmas tree. But these are just details too far off-topic.
How do we set aside the bone? Separate the fillet from the chicken along with the wing. Remove the skin. Cut the wing in half, cutting the end piece off. Remove the meat carefully from the other half. Now we have a bone and a fillet. This fillet consists of two parts – a larger and smaller one. Cut the small one off and set it aside.
The larger part is slightly thickened near the bone. Make slight notches (do not cut) on the periphery of the thicker oblique side of the bone.
Now when you tenderize it the fillet will have a uniform thickness. Cover the fillet with foil and use a wooden mallet to tenderize mostly around the thicker part. Take it out of the foil and carefully, with a very sharp knife, remove the tendons so they don't deform our culinary masterpiece during frying.
Thinly tenderize the small piece you had set aside. Salt the two pieces, sprinkle them lightly with black pepper and put half of that butter sausage, which we hid in the freezer in the middle of the large fillet. Then put the small fillet on top to cover it fully.
Carefully roll up everything tightly, so that the bone protrudes outwards and slightly upwards, and so that the oil does not leak out. In three suitable dishes, put the breadcrumbs, flour and beaten egg with milk. Heat the oil in a deep frying pan, which you need plenty of, because the meat has to be fried in an oil bath - almost like in a deep fryer.
Roll the cutlets first in the flour, shake them a little, roll them in egg, breadcrumbs, in egg again and again in the breadcrumbs.