What a wonderfully savoury dish! The chicken holds together beautifully when tied and got nicely browned on the outside while being moist and tender on the inside of the roll. I loved the flavor that the sherry imparted on the filling. I used a dry sherry and liked the taste, but might try a cream sherry next time for a bit better balance with the mushrooms and ham. (I think I'm looking for a hint of sweetness.) I used baby bella mushrooms and the filling was rich, earthy and full of deep flavor. I assembled the chicken about 10 hours before I cooked it and think that the time in the fridge helped the flavors in the filling combine. This is a very good recipe and I think it will be well loved in my kitchen for years to come.