Preheat the oven to 350 degrees F. Line a baking sheet with parchment paper or a silicone mat (for easy cleanup).
Combine the peanut butter, sugar, and egg in a medium bowl.
1 cup peanut butter, 1 cup sugar, 1 egg
Using a small cookie scoop, place balls of dough on the baking sheet.
Press on the balls of dough with a fork to flatten, making a criss-cross pattern. Then place in the oven and bake for 10 minutes.
Remove the baking sheet from the oven and place a large marshmallow on top of each cookie, then bake for 3 additional minutes.
Remove the baking sheet from the oven and press down with a non-stick spatual on each marshmallow to flatten it and distribute it over the cookie. Turn off the oven.
Sprinkle the chocolate chips over the flattened marshmallows (I didn't bother to worry about the ones that ended up on the parchment paper instead), then place the baking sheet into the still-hot oven for a minute or two for the chips to get melty.
1 cup mini chocolate chips
Remove the baking sheet from the oven, and allow to cool for 5 minutes. Remove from the baking sheet and enjoy!
You can use regular chocolate chips or even chunks of chocolate instead of the mini chocolate chips.
Chocolate lovers, you can also mix chocolate chips into the dough before baking for an even more chocolatey experience!
Store cookies in a single layer if possible, as the marshmallow tends to remain sticky and if the cookies are stacked they will stick together.