1cup(2 sticks) unsalted butter, at room temperature
1cupwhite sugar
2/3cupslight brown sugar, packed
2eggs
1teaspoonvanilla extract
3-¼cupsall-purpose flour
4(1-oz packages) hot chocolate mix (not sugar-free; a total of about 1 cup of hot chocolate mix)
1-¼teaspoonssalt
1-¼teaspoonsbaking soda
1cupmilk chocolate chips
1cupsemi-sweet chocolate chips
1 1/2cupsmini marshmallows, frozen (see note)
Instructions
Cream butter and sugars until smooth. Beat in eggs and vanilla until combined.
In a separate bowl, whisk together the flour, hot chocolate mix, salt and baking soda. Add the dry ingredients to the wet ingredients slowly until incorporated. The dough will be thick.
Fold in the milk chocolate chips and semi-sweet chips. Chill the dough for an hour. Chilling the dough allows the ingredients to blend and also makes a thicker cookie.
Preheat oven to 350 degrees F and line baking sheets with parchment.
Make cookie dough balls, around 1 1/2 tablespoons each, and place onto prepared baking sheets lined with parchment paper. Hand place the marshmallows in the cookies. Although I have a pic of folding them in, I've found this is the best way. Make sure to tuck the marshmallow inside the balls if you can so that you don't have marshmallows sticking to your pan. Bake for 10-12 minutes or until edges are golden brown. The cookies will still look soft. They will continue to cook on the cookie sheet as they cool. Let cool for 5 minutes before removing from pan. I love these warm. If your eating them after they have cooled you can warm them in the microwave for 10 seconds. Store in an airtight container.
Notes
Some readers have found that freezing the marshmallows to help keep their shape and to not let them melt out of the cookies. Source: slightly adapted from Tasty Kitchen . Changed measurements to be more clear and added mini marshmallows instead of white chocolate chips.