Combine the base ingredients in a large mixing bowl, adding oats, chia seeds, cream cheese, Greek yogurt, maple syrup, vanilla extract, and almond milk. Whisk until creamy. Let sit for 5-10 minutes.

If using frozen blueberries, microwave for 30 seconds, then mash until jam-like consistency.

Portion the oat mixture into jars, topping with blueberry mash or mixing it in for flavor.

Seal jars and refrigerate for at least 4 hours, ideally overnight, for flavors to meld and oats to soften.

Serve cold or warmed, adding toppings like granola, fresh berries, or nuts.