That's a tough question to answer and I expect you'll get a number of suggestions. Freshly baked artisan breads are always a priority. You don't need to bake them yourselves. Get them daily from Fulton Street Baking Company and/or Red Hen Bread and you'll have happy customers. Fresh and frozen sausages, ravioli of various types; a variety of fresh and frozen sauces (pomodoro, tomato cream, white cream, both red and white clam, etc.). Super-fresh and very high quality produce items are tough to keep in stock, but it would separate an operation from all of the other Italian specialty stores that carry many of the high-quality but ubiquitous cheese, sausage and antipasti that most better delis carry. You could do some research by shopping in north suburban Highwood. Visit Pastaficio -- particularly on a Saturday around noon. On Saturday you can buy some of their pre-made items from their steam table and sample their quality. Also shop Poeta's Food Market and Bacio's Deli for more ideas.