Put the oatmeal in a bowl or a lockable box for transport.
Pour the almond milk over it, it should cover the oatmeal as much as possible. If necessary, simply pour in a sip until it has the desired consistency.
Peel the banana, mash it with a fork and add to the oatmeal.
Now sprinkle 2 - 3 tablespoons of cocoa powder over it and stir everything well until you get a nice brown mixture.
If you want, you can now sweeten your overnight oats with 1 tablespoon of honey or maple syrup, etc. Depending on how ripe the banana is, it naturally has a sweet taste. Then stir everything thoroughly once and place in the refrigerator overnight.
The overnight oats with fine oat flakes can be consumed after a few minutes, as the fine flakes quickly soak up the milk. The longer you let it stand, the more mushy the consistency becomes.
Overnight soaking is recommended for coarse oatmeal.