In a mixing bowl, combine all base ingredients: rolled oats, chia seeds, yogurt, and milk. Add vanilla extract, salt, and matcha powder, then drizzle in maple syrup. Stir until the mixture is fully combined and uniform in color (about 2-3 minutes).

Using a spatula or whisk, blend the mixture thoroughly until oats and chia seeds are well-coated with matcha. Scrape down the sides of the bowl to incorporate all ingredients.

Transfer the mixture to airtight containers or jars and seal tightly. Chill in the refrigerator for at least 4 hours or ideally overnight.

Before serving, stir in a splash of milk if the mixture is too thick. Top with fresh fruits like berries or sliced bananas as desired.