Begin by making this a day ahead. Serve with a platter of Oysters on the half shell. This recipe comes from the November 2008 issue of Bon Appetit, courtesy of Southpark Seafood Grill & Wine Bar in Portland, Oregon.
Mix gin and thick cucumber slices in pitcher. Cover and chill overnight or up to 3 days.
Strain gin, discarding thick cucumber slices. Pour half of gin into cocktail shaker. Add 1 tablespoon vermouth, then fill shaker with ice. Shake vigorously; strain into three glasses. Repeat with remaining gin and vermouth.