Onion Frittata with Roasted Tomato and Cheddar

The Italian version of an omelet, in which the whisked eggs and the other ingredients go into a large pan at the same time, a frittata can be eaten warm or cold. Almost any kind of vegetable works well in a frittata. We love the sweetness and flavor of leeks and roasted onions. The original sandwich at ’wichcraft contained only the frittata and good, aged Cheddar cheese. Ben Bohen, a long-time collaborator, would have this sandwich as his regular breakfast—except that Ben would always add roasted tomato. He encouraged the staff to try it, and he encouraged the customers to try it, until eventually he converted us all and we put it on the menu forevermore with Ben’s roasted tomatoes.