Preheat your oven to 250°F (120°C). Line a large rimmed baking sheet (or two medium-sized baking sheets) with parchment paper or a silicone baking mat.
2. Prepare the Caramel Sauce:
In a medium saucepan over medium heat, melt the butter. Once melted, stir in the brown sugar and corn syrup. Bring the mixture to a gentle boil, stirring frequently. Let it boil for 3-4 minutes without stirring, until it thickens slightly and becomes bubbly.
Remove the pan from the heat and stir in the vanilla extract, baking soda, and salt (if using). The mixture will bubble up when you add the baking soda, so be careful!
3. Coat the Crispix Cereal:
Pour the Crispix cereal into a large mixing bowl (you may need to do this in batches if your bowl isn’t big enough).
Pour the caramel sauce over the cereal and gently toss to coat. Stir the cereal carefully with a spatula or spoon, ensuring all the pieces are covered with the caramel.
4. Bake the Caramel Crispix:
Spread the caramel-coated Crispix evenly onto the prepared baking sheet(s).
Bake in the preheated oven for 45-60 minutes, stirring every 15 minutes to ensure the cereal is evenly coated and doesn’t burn. The caramel will continue to cook and coat the cereal, turning it golden brown and crispy.
5. Cool the Caramel Crispix:
Once the cereal is golden brown and crispy, remove the baking sheet(s) from the oven and let the mixture cool for about 10 minutes on the sheet.
After it cools slightly, break the caramel Crispix into clusters and transfer it to a large bowl or storage container.
6. Store:
Store the Caramel Crispix in an airtight container at room temperature for up to 1-2 weeks. It should stay crunchy and fresh!
