Preheat oven to 375° F, and line a baking sheet with parchment paper.
In a large bowl, mix cereal, baking powder, and spice until combined.
Add the puree, egg, and vanilla. Stir until combined.
Drop 1 tbsp portions onto the lined baking sheet and flatten with the back of a spoon.
Bake for 10-12 minutes, checking regularly to avoid burning. If they look soft, bake for two more minutes. Cool completely.
Cut into bite-size piece appropriate for your little one’s age and stage.
Store in an airtight container for two days, or freeze for up to two weeks.