Add two teaspoons of brown sugar to a glass with espresso. Mix until combined.
In a tall glass or a jar, add ice cubes ¾ of the way.
Take an oat milk carton, shake for 3-5 seconds, and pour into a glass or a jar with ice, leaving enough space for espresso.
Pour espresso into a glass or a jar with milk and ice.
Add optional garnish, if preferred, like cinnamon or nutmeg.
Add a straw and serve immediately.
Notes
This iced oat milk latte will not be too sweet. It has the right amount of brown sugar to cut down the espresso's bitterness. If you prefer it sweeter, add more brown sugar.
Use smaller or larger glass or a jar based on your preferences. I used a 16 oz glass, equivalent to a grande/medium coffee cup.
I used the metal straw to be more environmentally friendly, which you can also clean easily.