In a large, microwave-safe bowl, combine the peanut butter and honey. Microwave on high for 1 minute. Remove from the microwave and stir until well combined.
Return the bowl to the microwave and heat for an additional 30 to 45 seconds, until the mixture is warm and easily stirrable.
Stir in the vanilla extract until fully incorporated.
Add the Cheerios to the bowl and gently stir until all the cereal is evenly coated with the peanut butter mixture.
Drop spoonfuls of the mixture onto a parchment-lined baking sheet or into cupcake liners. Allow them to set at room temperature. They should be firm enough to pick up within 30 minutes, but for best results, let them sit for a few hours to fully firm up.
Enjoy your Peanut Butter Cereal Bites as a quick snack or breakfast treat!