Add the bourbon whiskey, lemon juice, simple syrup, egg white and bitters to a cocktail shaker with no ice.
Put on the top and shake for 30 seconds. This is our dry shake. It helps our egg white better combine with the other ingredients and build a frothier topping.
Remove the top and add a handful of ice. Put the top back on and shake again for at least one minute to develop the frothy topping. This is our wet shake.
Once you've shaken the drink for at least one full minute to keep building that frothy topping, strain into a chilled glass.
If desired, garnish with a lemon twist. Not only does this make for a pretty presentation, but it adds a nice fragrance to every sip.
f you’re ready to upgrade your cocktail game, whip up this Boston sour and savor every sip. Thanks to that frothy foam and smooth flavor, it’s sure to be your new favorite bourbon cocktail.