In a small saucepan, over medium heat, melt butter. Once butter is melted add maple syrup. Stir to combine and heat syrup through just until it starts to bubble.
Take off heat and stir in vanilla and cinnamon
Pour over popcorn and quickly toss to coat.
Spread popped corn into a single layer of parchment paper and sprinkle with salt.
Allow to cool before eating. Store in an airtight container.