Line an 8 x 8-inch pan with parchment paper and grease generously. Set aside. Pour the cereal in a large mixing bowl.
In a microwave safe bowl or in a small saucepan, add the peanut butter, coconut oil, and syrup. Heat up or microwave until warm. Whisk together, to combine.
Pour the liquid mixture over the crispy cereal, and mix well, until combined. Transfer the mixture into the lined pan and press down using a rubber spatula.
Refrigerate the treats for at least an hour, to firm up.
* Any smooth nut or seed butter can be used. ** Any crispy keto/low carb cereal can be used.
To store: Crispy treats tend to become sticky and gooey when left at room temperature for too long. As such, it's best for them to be stored in the refrigerator, covered. They will keep fresh for up to 2 weeks. Let the treats sit at room temperature for 30 minutes prior to enjoying it.
To freeze: Place keto Krispie treats in a ziplock bag and store in the freezer for up to 6 months.