This beautiful bright red cocktail can be prepped almost entirely ahead of time. You’ll be infusing your gin of choice with fresh cranberry simple syrup and a whole lime peel. Use a Y-shaped peeler to carefully remove the peel from a lime, making sure to peel off as little white pith as possible (the pith can add a bitter flavor). Then, store your gin mixture in the refrigerator in an airtight container. We prefer storing it in a pitcher or large covered measuring cup, for easy pouring. The resulting infusion has the sweet-tart flavor of cranberries and the brightness of lime, and can be made up to a month in advance. To serve, you simply have to strain over ice and top with tonic.