Use real maple syrup for the best flavor; pancake syrup will not caramelize the same way.
For extra crunch, spread the coated popcorn on a parchment-lined baking sheet and bake at 250°F for 20 minutes, stirring once.
Adjust cinnamon to taste; add an extra pinch after tossing if you prefer a warmer spice profile.
Allow the popcorn to cool slightly before serving so the maple glaze can set properly.
Store leftovers in an airtight container at room temperature for up to 2 days.