750ML of your bourbon or rye whiskey of choice
2.5 oz simple syrup (1.5:1 ratio sugar/water)
40 dashes Peychaud’s bitters
40 dashes orange bitters (Fee Brothers or similar)

Pour the entire bottle of whiskey into a glass container that can be shaken or vigorously stirred. Add the simple syrup and shake/stir the mixture.

In a separate cup, combine and measure the bitters, and then combine that with the whiskey mixture. Shake again, and chill overnight in the refrigerator (do not freeze it).

To serve, shake the container to ensure there’s been no separation, and pour 1/5-2 ounces over a few cubes of ice.