Add the Greek yogurt, milk, frozen blueberries, maple syrup, and vanilla to a blender. Blend on high until completely smooth.
Divide the blended mixture evenly among 4 sealable jars. Add 2 tablespoons of chia seeds to each jar. (Alternatively, make one big batch in a large storage container to dish out as needed)
Stir right away, stirring well to fully incorporate the chia seeds before any gelling begins.
Seal and refrigerate overnight to set.
When ready to eat, stir, then top with more Greek yogurt and blueberries if desired.
