Austin chefs Larry McGuire and Lou Lambert are going roasting an entire 1,200-pound steer on a thousand acre ranch dotted with oak trees and Longhorns just outside of Austin. And of course you want to be there. Vaca y Vino promises to be one great five-hour dinner party, with delicious food, fine Argentine wine and local craft beer, and live tunes by Doug Strahan and the Good Neighbors. The event is inspired by South American chef Francis Mallmann and a…