Mix the chia seeds and almond milk in a jar or bowl, and let the mixture set for 5 minutes. Whisk or stir the mixture vigorously to evenly disperse the chia seeds.
Cover the jar, and transfer to the refrigerator to chill for at least 4 hours, or overnight.
In a small bowl, whisk together the cinnamon, ginger, nutmeg, cloves, chili powder, and black pepper.
Remove the chia pudding from the refrigerator, and stir in the pumpkin purée, dry spice mixture, vanilla extract, and maple syrup (if using). Serve garnished with coconut flakes.