In a cocktail shaker, place ginger, nutmeg, clove, rosemary, and honey simple syrup. Muddle the ginger well with the other ingredients, so that it is broken down a bit and will better infuse its flavor. Add in lemon juice, egg white, bourbon, and optional allspice. Do NOT add ice - simply shake these ingredients together well for a few moments. Then, re-open your cocktail shaker, and add ice to shake a second time around. Strain into a coupe glass and garnish with a rosemary sprig.