Peel shallot and cut into fine rings. Peel the cucumbers and cut into small pieces.
Heat butter in a pot, add shallot rings and fry. Add cucumber pieces and fry briefly. Deglaze with vegetable stock. Add lemon peel. Put a lid on the pot and steam cucumbers on low heat for 5 minutes.
Remove lemon peel from the pot. Mix flour in little cold water and add to cucumbers. Simmer for another 2 minutes. Mix sour cream with whipped cream and stir into cucumbers. Season to taste with salt and pepper.
Heat oil in a coated pan. Fry turkey cutlets for about 3-4 minutes, turn and fry for another 3-4 minutes. Chop sage leaves and add to pan. Salt and pepper turkey cutlets, remove from heat and deglaze with sherry.
Divide the turkey cutlets between two plates, pour the roast stock over them and serve together with the braised cucumbers.