Giant S’mores Skillet Cookie with Toasted Marshmallow Fluff Step-by-step instructions

Before you start

Before starting, heat the oven to 350°F (175°C) and lightly butter an 8-inch cast iron skillet. Measure out all ingredients; the dough comes together quickly.

Have the marshmallow fluff, chocolate bar, and mini marshmallows ready to top the cookie as soon as it comes out of the oven. If using a kitchen torch, ensure it's filled and ready.

Instructions

Make the Dough

1. 1Mix the Cookie Dough
   In a medium bowl, whisk the melted butter, brown sugar, and white sugar until combined. Whisk in the egg and vanilla extract until smooth. Add the flour and baking soda, and fold with a rubber spatula until just combined. Fold in the dark chocolate chunks.
   Look for The dough will be thick and slightly glossy, with no streaks of flour.
   Tip Do not overmix once the flour is added; overworking the dough can make the cookie tough.
2. 2Press Dough into Skillet
   Lightly butter an 8-inch cast iron skillet. Press the cookie dough evenly into the skillet, smoothing the top with the spatula.
   Look for The dough should reach the edges of the skillet in an even layer.
   Tip Using a slightly damp hand can help press the dough without sticking.

The dough should be thick and slightly glossy, with no streaks of flour. It should hold together when pressed. The chocolate chunks should be evenly distributed. The skillet should be filled to the edges with an even layer of dough.

Bake and Top

3. 3Bake the Cookie
   Heat the oven to 350°F (175°C). Bake the skillet cookie for 15 minutes, until the edges are crisp and golden and the center is set but still soft.
   Look for The edges will look dry and lightly browned; the center will feel slightly firm to the touch.
   Safe temperature 160°F (71°C) internal temperature (egg dishes)
   Tip Baking time may vary; start checking at 12 minutes.
4. 4Top with Marshmallow Fluff and Chocolate
   Remove the skillet from the oven and immediately spread the marshmallow fluff over the warm cookie. Scatter the broken milk chocolate bar pieces and mini marshmallows over the fluff.
   Look for The fluff will soften and spread easily; the chocolate pieces will begin to melt.
   Tip Work quickly while the cookie is hot to help the toppings melt.
5. 5Torch the Topping
   Using a kitchen torch, toast the marshmallow fluff and mini marshmallows until golden brown in spots. If you do not have a torch, place the skillet under the broiler for 1 to 2 minutes, watching closely.
   Look for The marshmallows will puff and develop charred, golden patches.
   Tip Keep the torch moving to avoid burning one spot.

The baked cookie will have golden, crisp edges and a soft center. The marshmallow fluff will spread easily over the warm surface, and the chocolate pieces will soften. The mini marshmallows will add a fluffy texture before toasting.

Torch and Serve

6. 6Serve Warm
   Sprinkle graham cracker crumbs over the top. Scoop out portions with a large spoon, making sure to get some of the toasted marshmallow and melted chocolate in each bite. Top with a scoop of vanilla ice cream if desired.
   Look for The cookie will be gooey and stretchy, with melted chocolate and toasted marshmallow in every spoonful.
   Tip Serve immediately while warm for the best texture.

The marshmallow topping will be toasted with golden-brown spots and a slightly charred aroma. The chocolate will be melted and gooey. The cookie should be served warm, with the toppings stretchy and the edges crisp.

Common mistakes

One common mistake is overbaking the cookie, which makes it dry and cakey. Start checking at 12 minutes and remove it from the oven as soon as the edges are set.

Another is pressing the dough too thin; if it doesn't reach the edges, the cookie will be too thin in the center.

Also, avoid using cold butter; melted butter is essential for the chewy texture. When torching, keep the flame moving to prevent burning.

How to tell it’s done

The cookie is done when the edges are golden brown and crisp, and the center is set but still soft—a toothpick inserted near the center should come out with a few moist crumbs, not raw batter.

The internal temperature of the egg in the dough should reach 160°F (71°C) to ensure it's fully cooked. The topping should be toasted to a deep golden brown with some charred spots for flavor.

• Egg dishes: 160°F (71°C) in the thickest part