Preheat your oven to 350°F and prepare your baking sheet by lining it with parchment paper.
Cream together the softened butter, brown sugar, and granulated sugar until light and fluffy.
Beat in the pumpkin puree, egg, and vanilla extract until well combined. Add food coloring if using.
In a separate bowl, whisk together the flour, baking soda, pumpkin pie spice, and salt.
Gradually add the dry ingredients to the wet mixture, mixing until just combined.
Gently fold in the chocolate chips, mini vegan marshmallows, and broken graham cracker pieces.
Using a small cookie scoop or spoon, drop rounded tablespoons of dough onto your prepared baking sheet.
Top each cookie dough ball with extra vegan marshmallows, chocolate chips, and/or pieces of graham crackers.
Bake for about 12 to 14 minutes or until the edges are golden but the centers remain soft.
Allow the cookies to cool on the baking sheet for a few minutes before transferring them to a wire rack.
Serve your pumpkin s'mores cookies at room temperature.