To a mason jar or small bowl, add almond milk, chia seeds, peanut butter, and maple syrup (or other sweetener) and stir with a spoon to combine. The peanut butter doesn't need to be completely mixed with the almond milk (doing so leaves swirls of peanut butter to enjoy the next day).
Add oats and stir a few more times. Then press down with a spoon to ensure all oats have been moistened and are immersed in almond milk.
Cover securely with a lid or plastic wrap and set in the refrigerator overnight (or for at least 6 hours).
The next day, open and enjoy as is or garnish with desired toppings (see options above).
Overnight oats will keep in the refrigerator for up to 2 days, though best within the first 12-24 hours.
*Overnight oats adapted from Eating Bird Food (one of my many girl crushes). *Prep time reflects preparation and overnight soaking. *The first, fifth, and last images reflect two servings (double ingredients) with additional chia seeds and peanut butter. *Nutrition information is a rough estimate.