Preheat your oven to 375 degrees F and line a large baking sheet with parchment paper, set aside.
Cream together your butter, sugar and brown sugar until fluffy.
Beat in your eggs and vanilla extract until combined.
In a separate bowl, whisk together your flour, baking powder, baking soda, and salt. Slowly mix your dry ingredients into your butter mixture until well combined.
Mix in your chocolate chips and mini marshmallows.
Using a large cookie dough scoop, place your cookie dough balls on your prepared baking sheet, leaving a few inches in between for cookies to spread.
Bake for 8-10 minutes or until cookies have JUST started to brown.
Allow to sit for at least 5 minute on baking sheet before transferring to a wire cooling rack to fully cool. Enjoy!
