To a small mixing bowl add cacao powder (sift first to reduce clumps), maple syrup, ground cinnamon, salt, and vanilla and whisk to combine. Then add a little dairy-free milk at a time and whisk until a paste forms. Then add remaining dairy-free milk and whisk until smooth.
Add chia seeds and whisk once more to combine. Then cover and refrigerate overnight, or at least 3-5 hours (until it's achieved a pudding-like consistency). It may also be helpful to give the mixture an extra whisk/stir once it has been in the refrigerator for 30-45 minutes.
Leftovers keep covered in the fridge for 4-5 days, though best when fresh. Serve chilled with desired toppings, such as fruit, granola, or coconut whipped cream.
*Nutrition information is a rough estimate calculated without optional ingredients or toppings, with the lesser amount of maple syrup, and with almond milk (not coconut milk). *Prep time reflects chilling for the least amount of time (3 hours). *Recipe loosely adapted from Pop Sugar.