Preheat oven to 350 degrees F and line a baking sheet with parchment paper.
Pour cereal into a large bowl, then set aside.
In a medium-sized saucepan, add brown sugar, butter, and corn syrup. Stirring constantly, bring mixture to a boil then continue cooking for 1 more minute.
Remove pan from heat and stir in vanilla and baking soda. Mixture will bubble and expand.
Pour the mixture over the cereal and toss to evenly combine.
In a small bowl, sift together granulated sugar and cinnamon, then sprinkle over the cereal. Toss again until evenly coated.
Transfer cereal to the prepared baking sheet and bake for 8 minutes, stirring halfway through.
Allow cereal to cool then break into bite-sized pieces. Store in an airtight container.
