Tall windows flood the vast dining room with natural light, illuminating a minimalist mix of rectangular and round tables—each ringed by tasteful, Modernist chairs—beneath a grid of industrial light fixtures and exposed wooden beams. Is this the city’s hottest new restaurant that everyone’s been talking about, the one with the locally sourced ingredients served on artfully presented plates? No, it’s the new T.G.I. Friday’s. “It was like you opened the door to your grandmother’s attic, and the stuff was just tumbling down the steps.†That’s right, Friday’s, the once-popular singles bars and burger joints found in the parking lots...