Combine sugar, maple syrup, and vanilla extract in a medium saucepan on the stove top, stirring occasionally. Heat over medium heat until the mixture comes to a roaring boil and the sugar dissolves. Take off the heat and let sit for 5 minutes.

Add the popped popcorn and M&Ms to a large mixing bowl. Pour the simple syrup over the popcorn mixture and use a spatula to gently mix.

Coat your hands with non-stick cooking spray and start forming ½ cup-sized popcorn balls.

Let the popcorn balls cool on a baking sheet lined with parchment paper.