Preheat the oven to 350°F. Line two large baking sheets with parchment paper of a silicone baking mat. Set aside.
Combine butter and brown sugar in a large bowl or the bowl of a stand mixer and beat together on medium speed until smooth and creamy.
1 cup unsalted butter, 1 cup light brown sugar
Add vanilla extract and eggs and continue mixing until combined.
2 large eggs, 1 teaspoon vanilla extract
Stir in the sifted hot chocolate mix (reserving the marshmallows for the topping) and the unsweetened cocoa powder just until combined.
¾ cup hot chocolate mix with marshmallows, ¼ cup unsweetened cocoa powder
In a separate medium bowl, whisk together the all purpose flour, baking powder and salt.
2 ¼ cups all-purpose flour, 1 teaspoon baking powder, ½ teaspoon fine sea salt
Add half of the flour mixture and mix on low speed until combined. Add remaining flour mixture and mix just until combined being careful not to over mix.
Stir in chocolate chips just until combined.
1 cup semi sweet chocolate chips
Use a medium cookie scoop or scoop out 1½ tablespoons of cookie dough and place on prepared cookie sheet, about 2 inches apart. Repeat with remaining dough.
Press four or five of the reserved marshmallows from the hot chocolate mix onto the top of each cookie dough ball.
Bake for 10 to 11 minutes until lightly golden on the edges.
Remove from the oven and let rest on the baking sheet for 5 minutes. Now is a great time to add a few chocolate chips to the top of each cookie. Just press lightly when adding the chips.
Transfer the cookies to a cooling rack to cool completely or enjoy warm!