The 52-year-old New York native was not at the restaurant that was located at the top the North Tower of the World Trade Center because he had decided to order reading glasses before going to work that morning.
After the attack he helped to raise more than $20 million for families of people who had worked and died at the restaurant. He has also kept busy with writing, teaching and doing television work.
Lomonaco, who has been known for his creative update of American cuisine since his days as the head chef at '21' in the early 1990s, opened his interpretation of the American steakhouse, Porter House New York, in 2006 to wide acclaim.
Find out more about how he recovered from this tragedy and his love of cooking.
Q: What has been your motivation after 9/11?
A: "I said to myself on Sept 12th that I will continue to work in the restaurant business in New York because it's what I want do and what my friends want me to do. It's really a tribute to my colleagues, my co-workers, my friends whom I lost that day."
Q: What does your new restaurant mean to you?
A: "I think in general many of us (from Windows) have really gotten on with our lives, picked up the pieces, rebuilt and have been able to construct new chapters so Porter House is really a new chapter in my life."
Q: What is your view on grass-fed versus corn-fed beef?
A: "Beef is primarily finished on corn toward the end of the process of raising beef. The corn puts a higher degree of marble and fat, which results in prime beef. Most of the cattle are fed part of the time on grass. The argument has died down because corn-fed beef grades prime because of the marble and because of the tenderness and texture."
Q: Seafood features prominently at Porter House. Why?
A: "I think a great balance to a great steakhouse is also great cuts of fish cooked and prepared with the same gutsy, generous feelings that we associate with great prime beef."
Q: What do you cook when you are home?
A: "I like to make a roasted chicken, a pasta dish, homemade pizza or a big salad with grilled meats or fish in it. I also cook a lot of home-style Italian dishes that I and my wife grew up with."