Rooftop Chef officially launched last month with dinner for 30 atop the Tate. Candles flickered. Wine flowed. The stilettos were out in force: Blahnik, Louboutin, Choo. Guests, including Vanity Fair creative development editor David Friend and Hana Nitsche, the Czech model and on-again-off-again girlfriend of Russell Simmons, sat under a pergola, eating crostini, PEI mussels, red and yellow grape tomato salad. The genial Mr. Coli in pristine chefs’ whites grilled lamb chops and hangar steaks.