In a container or bowl, mash the ripe banana until mostly smooth. A few small lumps are okay.
Whisk in the oat milk and canned full-fat coconut milk (or just one, if you prefer) along with the chia seeds, maple syrup, spices, and salt.
Let the chia pudding sit at room temperature for 10 minutes, then give it another good stir. This helps prevent the chia seeds from sinking to the bottom and breaks up any spice clumps, making sure everything is evenly mixed and creamy.
Cover with a lid and place in the fridge overnight or for at least 6 hours. The chia seeds need time to soak up the liquid to become nice and creamy.
Give it a quick stir before serving. Top with extra banana slices, drizzle of almond butter, a sprinkle of cinnamon, or whatever toppings you love. Enjoy!