01 - In a medium bowl or jar with a lid, combine the rolled oats, milk, Greek yogurt, chia seeds, maple syrup, lemon zest, lemon juice, and vanilla extract. Stir until evenly incorporated.
02 - Gently fold the blueberries into the oat mixture, distributing them throughout without crushing.
03 - Cover the bowl or jar tightly and refrigerate overnight, or for a minimum of 6 hours, allowing the oats to soften and absorb the liquid.
04 - In the morning, stir the oats well. If the mixture is too thick, add a splash of milk and stir until the desired consistency is reached.
05 - Top with chopped nuts, additional blueberries, and extra lemon zest as desired. Serve chilled.