In a heatproof bowl, muddle the lemon zest with the sugar. Let stand for 1 to 2 hours. Muddle again, add 8 ounces boiling water and stir until the sugar dissolves. Strain into a warm heatproof bowl and stir in the whiskey. Add the remaining 32 ounces of boiling water and garnish with the studded lemon slices and nutmeg.