In a mason jar (1 pint works great) add the oats, cinnamon, chia seeds, and peanut butter, add half the milk and mix completely. Add the remaining milk and stir. Top with frozen berries (they will defrost by morning) and drizzle with honey (if desired).

Place the lid on the mason jar and refrigerate overnight (or up to several days). In the morning, add additional liquid if you'd like to achieve preferred consistency.