01 - In a medium bowl or jar, combine the oats, milk, Greek yogurt, brown sugar, cinnamon, and vanilla extract. Stir thoroughly until all ingredients are well incorporated and the oats are evenly distributed.
02 - Cover the container tightly with a lid and refrigerate for at least 8 hours or overnight to allow the oats to soften and absorb the liquid, creating a creamy consistency.
03 - In the morning, remove from refrigeration and stir the oats well. If the mixture appears too thick, add a splash of milk to reach your preferred consistency.
04 - Top with banana slices, chopped nuts, and fresh berries or apple slices if desired. Serve chilled straight from the refrigerator.