In a medium-sized mixing bowl or mason jar, combine the oats, milk, Greek yogurt, matcha powder, chia seeds, honey, and vanilla extract. Stir well to ensure all ingredients are thoroughly mixed.

Check for a thick but pourable consistency. Adjust with a little more milk if too thick, ensuring a smooth blend free of clumps.

Cover the mixture and place it in the refrigerator. Chill for at least 2 hours, ideally overnight, to allow the oats to absorb liquid and thicken.

Once ready to serve, check the consistency again and adjust with milk or chia seeds as needed to achieve desired creaminess.

Customize with your favorite toppings like sliced bananas, fresh berries, granola, or nut butter before enjoying.