Preheat the oven to 350F and line baking sheet with parchment paper. Into a mixing bowl add 1 ¾ cups of flour, ¼ cup cocoa powder, ½ teaspoon baking soda and give it a good whisk.
Using a sand mixer with paddle or whisk attachment, beat 1 cup of butter with ⅓ cup of sugar and ½ cup of brown sugar. Beat until fluffy.
After add 1 egg, 2 tablespoons water and 1 ½ teaspoons vanilla extract. Beat until everything is combined.
Now, add flour mixture, beat until combined. Lastly, stir in mini chocolate chips.
Using small ice cream scooper, scoop cookie dough onto a baking sheet lined with parchment pepper. Press 3 mini marshmallows into the dough and bake for 9-10 minutes.
If you want the marshmallows to have a golden burnt color broil on high for few seconds or use a torch to roast the marshmallows to give them that fire roasted color. Let cool and enjoy!
Notes
To get that perfect chewy texture, it's best to slightly under-bake them. This will give them a slightly crispy exterior and a soft center that's sure to impress.
For consistent sizes, I highly recommend using a cookie scoop. This will help you make sure every cookie is the same size, which means they'll all bake evenly.
Last but not least, to avoid any sticky situations, I suggest using a silicone baking mat or parchment paper. With marshmallows and melted chocolate in the mix, things can get pretty sticky. But with a good non-stick surface, your cookies will come out perfectly every time. Happy baking!