Fill a small old-fashioned glass with cracked ice and set aside. In another small old-fashioned glass, put the lump of sugar and just enough water to moisten it. With a spoon, crush the sugar, then add the Peychaud’s bitters, Angostura bitters, whiskey, and several ice cubes. Stir. Never use a shaker. Empty the first glass of ice, add the Herbsaint or Pernod, twirl the glass around, and shake the liqueur out. Strain the whiskey mixture into the glass, twist in the lemon peel, and serve immediately.