Spray a 6 quart slow cooker with non stick cooking spray.

Add cereals, peanuts and pretzels.

In a small bowl, combine butter, brown sugar, syrup, vanilla extract and cinnamon.

Pour butter mixture over cereal mixture and gently stir to combine.

Cook, uncovered in slow cooker, on high for 1.5 hours. Stir gently every 30 minutes, making sure to stir from the bottom of the slow cooker.

Change heat setting to low and let cook another 20 minutes, stirring one more time halfway through.

Transfer to a parchment paper lined baking sheet and let cool.

Sprinkle in M&M'S once cool and serve.