1.5 tablespoons unsweetened cocoa powder – sifted if lumpy
0.25 teaspoons vanilla extract
0.75 cups whole milk – well chilled
1 cups ice cubes
whipped cream – lightly sweetened (for serving)
chocolate syrup – for drizzling on top (for serving)
Instructions
Brew the espresso so it is fresh and hot, yielding about 2 ounces.
In a heatproof measuring cup or small bowl, combine the hot espresso, granulated sugar, and unsweetened cocoa powder.
Whisk the mixture until the sugar and cocoa powder are completely dissolved and you have a smooth chocolate espresso base, 30–60 seconds; whisk in the vanilla extract.
Let the chocolate espresso mixture cool at room temperature for 3–5 minutes until just warm, so it does not melt the ice excessively.
Fill a 12-ounce glass about three-quarters full with the ice cubes.
Pour the cooled chocolate espresso mixture over the ice, stirring briefly to begin chilling it.
Add the cold whole milk to the glass, pouring slowly and stirring gently until the drink is evenly mixed and the color is uniform.
Taste the iced mocha and adjust the sweetness by stirring in a little more sugar if desired, letting it dissolve as you stir.
Top the iced mocha with a generous swirl of lightly sweetened whipped cream.
Drizzle chocolate syrup over the whipped cream, insert a straw, and serve the iced mocha immediately while well chilled.