Add milk and yogurt to the blender first so the blades have liquid around them when blending starts.
Add pumpkin, maple syrup, almond butter, cinnamon, ginger, nutmeg, salt and vanilla.
Place the frozen banana pieces on top, separating any pieces that have frozen into a solid block.
Start on low, increase to high, and blend for 45 to 60 seconds until completely smooth, stopping safely to scrape if needed.
For a thinner smoothie, add milk one tablespoon at a time. For a colder, thicker drink, add a few more frozen banana slices.
Pour immediately into two glasses, dust lightly with cinnamon if desired, and serve before the frozen fruit melts.