Preheat oven to 350°F (175°C) and line a baking sheet with parchment paper.
Mash the banana in a mixing bowl until smooth.
Add pumpkin puree, peanut butter, and egg (if using), then mix until combined.
Gradually add rolled oats and cinnamon, stirring to form a dough.
Roll the dough out on a floured surface to about ¼ inch thick.
Use cookie cutters or cut into small squares.
Place treats on the lined baking sheet, leaving space between them.
Bake for 12-15 minutes or until the edges turn golden brown.
Let the treats cool completely before serving to your dog.
Store in an airtight container at room temperature for up to 1 week or refrigerate for up to 2 weeks.
