South Philly’s Birchtree Catering is throwing a launch party this Thursday, 6-9 p.m. at the Fleisher Art Memorial, and it has all the makings of a good time: Dock Street’s Summer Session wheat beer, a “triple shot cold soup station,” with Caramelized Carrot and Ginger, Citrus and Beet and Clean Green Cucumber Soups and bunches of raffles ranging from Buttercream Cupcakes to Chaddsford Winery to South Philly Comics. And it’s all free. Just RSVP.