Sazerac Cocktail

Put the sugar cube in a mixing glass with just enough water to moisten it. Use the back of a barspoon to crush the cube. Add the rye, both bitters, and ice and stir until chilled, about 30 seconds. Add the absinthe to a chilled Old Fashioned glass. Turn the glass to coat the sides with the absinthe, then pour out the excess. Strain the rye mixture into the absinthe-coated glass. Twist and squeeze the lemon peel over the glass. Rub the rim of the glass with the peel, drop it into the cocktail, and serve.