In a bowl or mason jar, combine the chia seeds, protein powder, milk, and, if you'd like, a pinch of salt and a little maple syrup. Stir well with a spoon, or seal the jar and give it a good shake until everything is fully mixed.
Let the mixture rest for 5-10 minutes, preferably in the fridge.
Use a spoon or fork to stir the pudding from bottom up. This helps break any clump of chia seeds and protein powder that may have formed at the bottom.
Close the jar with lid or cover the bowl with plastic wrap and refrigerate for at least 2 hours or overnight, until the protein seeds have thickened into a pudding.
Give it a stir, adjusting the texture with a splash of milk if necessary. Serve with your favorite toppings, such as fresh berries and nut butter.