After waiting several months for Lockhart Smokehouse's opening day, the Posse made its way across the ice-packed Houston Street viaduct today for lunch in the OC. We were not disappointed. Posse pitmaster Marshall Cooper, his son Mark & I sampled the meat spread shown above. We ordered brisket, shoulder clod, a pork chop and Kreuz jalapeno sausage. Jim Rossman and Gary Barber joined in on the meatfest as well. There was nothing left but grease-soaked butcher paper when we were done. It was their second day of business, unfortunately we were too jammed at work to get away on opening…