Trader Joes and Winco sell 5 oz packages of pancetta already diced. Trader Joes also sells a package of prechopped mirapoix (celery, onions, and carrots). If you use this, estimate four cups for this recipe. The jar of chestnuts is typically a seasonal item, so you may need to purchase this item first to determine if you'll even have it on-hand to make. (I found the last jar at Cost Plus World Market.)