I made this using Amaro Montenegro because I had no Averno on hand. Not good, a bit sharp really. But I suspect the real problem was the grappa. Is there a question mark over Grappa di Moscato acquired from the bargains section of a Napoli supermarket?????
Had this for an after-dinner/evening sipper, and it was perfect. The hint of grappa is there, but it has a herbal sweetness which is perfect for the evening.