Make the lavender cold foam: Add the heavy cream, milk, lavender syrup, and food coloring (if using) to a small jar or container. Froth for 10-20 seconds with a milk frother, until the mixture is well combined. Set aside.
Add the oat milk, vanilla syrup, and matcha powder to a large container. Using a milk frother or matcha whisk, stir for 1-2 minutes until the matcha is well combined in the oat milk.
Pour the matcha oat milk into a tall glass over ice, then top with the lavender cold foam. Drink up!
