PREPARATION
Preheat oven to 350º F and line 1-2 large baking sheet(s) with parchment paper.
Place cereals in a large bowl and set by your workstation. Combine sugar and cinnamon in a medium bowl and set aside.
Combine brown sugar, butter, and corn syrup in a medium saucepan over medium heat and bring to a boil. Cook, stirring continuously, for 1 minute.
Remove mixture from heat and stir in baking soda, then pour mixture over cereal.
Toss everything together until evenly coated, then transfer cereal to lined baking sheet. Sprinkle cinnamon sugar mixture over the cereal and transfer baking sheet(s) to oven.
Bake for 6 minutes, then flip cereal over and cook for another 2-3, or until cereal is golden brown.
Remove mixture from oven and let cool, then break up cereal and store in an air-tight container.
Break into pieces and enjoy!