In Southern California, the farmers' markets are bursting with stone fruit. But after you've made a few peach cobblers, thrown some nectarines on the grill, and eaten plum after ripe, juicy plum, what's left? Stone fruit cocktails. Santa Monica's Basement Tavern at the Victorian has devoted this summer season to all things stone fruit, culled primarily from the market held Sundays in the bar's parking lot. Here's how to make these delicious drinks at home.