In a medium saucepan, combine blueberries and maple syrup. Cook over medium heat for about 1 minute until softened. Mash lightly and cool before refrigerating.

In a large mixing bowl, stir together oats, chia seeds, and water or milk. Add maple syrup, Greek yogurt, vanilla extract, and salt. Mix thoroughly and refrigerate for at least 3 hours or overnight.

Layer blueberry mixture in a jar or bowl, followed by the oats. Top with additional blueberries, nuts, or seeds. Serve immediately or store in the fridge.