One of my favorite places to eat when I am in NYC is Pennsylvania 6 on 31st Street. The restaurant is centrally located, it is literally around the corner from Madison Square Garden. The restaurant caters to those who love American fare, but the menu ranges from an incredible crab mac and cheese, a luscious 14 ounce steak, succulent salmon and a tender organic chicken. They also feature a wide pizza menu.
The portions are hearty, beautifully plated and worth the NYC sticker price. My favorite has to be their lamb chops and their crab mac and cheese, however, I don't think I have ever had a bad meal here.
P.S.: the restaurant can get a little loud after 5 as the Manhattan crowd heads in for happy hour but the food is so worth it.
P.S.S.: Do make reservations if you intend to have dinner at Penn 6.