How to Make It
Combine simple syrup, figs, and ginger in a small saucepan. Bring to a boil over medium. Reduce heat to low, and simmer until figs are softened, about 5 minutes. Remove from heat, and let cool 30 minutes. Refrigerate mixture, covered, 8 hours or overnight. Pour mixture through a fine wire-mesh strainer into a bowl; discard solids. Store in an airtight container up to 1 week.
Place mezcal in a pitcher. Pour 11/4 cups fig-ginger syrup through a fine-mesh sieve into pitcher, followed by lemon juice and 3/4 cup water. Refrigerate until chilled, 2 hours or up to overnight. Stir before serving. Pour over large ice cubes into rocks glasses. Garnish servings with freshly grated nutmeg.