1. Preheat your oven to 350°F and line two baking sheets with parchment paper.
2. In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until the mixture is light and fluffy, about 3-4 minutes.
3. Add the eggs one at a time, beating well after each addition, then mix in the vanilla extract.
4. In a separate bowl, whisk together the flour, baking soda, baking powder, salt, and cocoa powder.
5. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
6. Gently fold in the chocolate chips and mini marshmallows. The dough should be thick and slightly sticky.
7. Using a cookie scoop or tablespoon, drop dough onto the prepared baking sheets, leaving about 2 inches between cookies.
8. Bake for 10-12 minutes, or until the edges are lightly golden. Keep an eye out for the marshmallows—they should be just melted and gooey.
9. Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.

From years of baking with my kids, I’ve learned that letting them scoop the dough is a fun way to involve them in the process. Plus, it makes for some wonderfully imperfect cookies that are perfect in their own way.