Brew 1 cup of hot espresso using an espresso machine or stovetop Moka pot. The thermal shock from hot espresso meeting cold ice is crucial for optimal foam formation, so don't let it cool completely.
In a cocktail shaker, combine the hot espresso, ¼ cup maple syrup, ¼ cup heavy cream, ½ teaspoon vanilla extract, and a pinch of salt (⅛ teaspoon).
Add 1 cup crushed ice to the shaker. Seal tightly and shake vigorously for 15-20 seconds until the outside of the shaker becomes frosty. Strain out the ice, then shake again without ice for another 10 seconds. This reverse dry shake method creates maximum aeration and foam stability.
Line the rim of your glasses with maple syrup, then dip it into cocoa powder to create an elegant garnish. Strain the espresso mocktail into your prepared glass. The foam should sit proudly on top. Dust with additional cocoa powder for garnish.
Notes
Hot Espresso Is Best: Hot espresso creates better foam than chilled.
Shake Well: Vigorous shaking incorporates air and creates smaller bubbles, which produce a better, more stable foam.
Foam Stability Hack: If you want an even more stable foam, I have a hack for you! Add 1 tablespoon of aquafaba (water from canned chickpeas) before shaking. The saponins in chickpea liquid create a very stable foam without affecting the flavor.