Step 1

Make 2 shots of espresso in an espresso machine: Add 2 ounces (1/4 cup) water to the boiler, then firmly pack 2 tablespoons (2 shots) finely ground dark coffee beans into the portafilter. Attach the portafilter to the machine and place a cup or carafe underneath the drip spout. Turn the espresso machine on and brew the espresso, 25 to 45 seconds depending on your machine. Pour the espresso into a coffee cup.

Step 2

Make the steamed milk and foam: Pour 4 ounces (1/2 cup) whole or unsweetened oat milk into a small pitcher. Using the steam wand on the espresso machine, hold the milk pitcher so the wand nozzle is just below the surface of the milk and against the side of the pitcher. Turn on the wand and froth the milk until it doubles in volume, moving the pitcher higher and lower so the wand can evenly foam the milk, 60 to 90 seconds. The bubbles should get smaller in size.

Step 3

Swirl the foamed milk in the pitcher. Pour the foamed milk over the brewed espresso until the foam reaches the brim of the cup. Half of the milk will settle while the foam sits on top. Lightly dust the top with 1/8 teaspoon cocoa powder or ground cinnamon if desired.