Adapted from Lee Hefter, executive chef of Spago Beverly Hills. Verjus is a natural juice of seedless, unripened green grapes. Sichuan peppercorns are reddish pink and have a unique flavor. Once you make the various components, final prep and service are easy. And since the squab needs an hour of sitting in the rub, you can make the puree and the cabbage while the squab rests in its rub.