01 -
Start by preheating your oven to 350°F (175°C). While it's warming up, line a baking sheet with parchment paper to prevent the cookies from sticking.
02 -
Grab a medium bowl and whisk together the flour, cocoa powder, baking soda, and salt. This helps distribute the leavening agents evenly and breaks up any cocoa powder lumps for a smoother dough.
03 -
In a large bowl, beat the softened butter with both the granulated and brown sugars until the mixture becomes light and fluffy - this usually takes about 2-3 minutes with an electric mixer. The combination of two sugars gives these cookies the perfect balance of sweetness and chewiness.
04 -
Crack in the egg and pour in the vanilla extract, then mix everything until well combined. Make sure to scrape down the sides of the bowl so everything gets incorporated evenly.
05 -
Gradually add your dry ingredient mixture to the butter mixture, stirring just until everything comes together. Be careful not to overmix, or your cookies might turn out tough instead of tender.
06 -
Using a cookie scoop or a couple of spoons, drop about 2 tablespoons of dough onto your prepared baking sheet for each cookie. Space them about 2 inches apart since they'll spread as they bake.
07 -
Slide your cookies into the preheated oven and bake for 10-12 minutes, or until the edges look set but the centers still seem slightly soft. This gives you that perfect chewy texture when they cool!
08 -
Here comes the fun part! Take the cookies out of the oven and quickly press a marshmallow half into the center of each warm cookie. The heat from the cookies will help the marshmallows stick. Pop the tray back into the oven for another 2 minutes, just long enough for the marshmallows to puff up without completely melting away.
09 -
Let the cookies rest on the baking sheet for about 5 minutes - they're fragile when hot and need a moment to set up. Then transfer them to a wire cooling rack to finish cooling completely. The marshmallows will deflate a little as they cool, creating the perfect little divot for your ganache.
10 -
Once the cookies are completely cool, drizzle them with chocolate ganache in a pretty swirl pattern. You can use a spoon or a piping bag with a small tip for more control. Let the ganache set for a few minutes before serving your double chocolate marshmallow masterpieces!