In a medium bowl, combine the rolled oats, almond milk, maple syrup, chia seeds, cinnamon, nutmeg, and salt. Stir well until all ingredients are fully incorporated.
Fold in the diced apple and Greek yogurt, mixing gently to avoid breaking down the apple pieces.
Divide the mixture evenly into two jars or containers with lids.
Sprinkle the chopped walnuts on top of each jar.
Seal the jars and refrigerate overnight (or for at least 4 hours) to allow the oats to absorb the liquid and flavors to meld.
In the morning, give the oats a good stir. If the mixture is too thick, add a splash more almond milk to reach your desired consistency.
Optional: Top with additional diced apples, a drizzle of maple syrup, and a sprinkle of cinnamon before serving.
Notes
Serve in clear glass jars to showcase the layers, and garnish with a slice of fresh apple or a sprinkle of extra cinnamon.
Keyword apple pie, breakfast, healthy, overnight oats