My wife, baby and I are in Manhattan for 2 weeks, visiting from Seattle. Based on the recommendation in the The Chowhound Guide and Frank Richman's book (Fork it Over) we headed over to Queens for a Mozarella sandwich at Leo's Latticini, and it was killer. About a half pound of beautiful fresh cow milk mozarella on a nice crispy roll with roasted red peppers and mushrooms. Nothing complicated, but the cheese is nice and sweet as is the atmosphere at the store. And then we went into Mama's Backyard which is their bakery and had a killer Mille Feuille (I think that is what it is called) - crispy layers of filo around a lemony mascarpone filling.
We also tried to walk over to the Corona Heights Pork Store for an eggplant parmesan hero, and they are out of business! Sorry for the bad news. There was a sign up saying it has been repossesed by the landlord. It seemed like the owner and his friends were having a bbq in the park across the street, so it looked like a very recent happening. No info on whether this is permananent or just a temporary situation.