Cookie Dough Brownie Skillet

Preheat oven to 350°F (175°C). Grease the bottom and sides of a 12-inch cast iron skillet with butter and set aside.

**For the Brownie:**

1. In a saucepan, melt unsweetened baking chocolate, semi-sweet chocolate chips, and 2/3 cup butter over low heat, stirring frequently until smooth. Remove from heat and cool slightly.
2. In a large bowl, beat 1 3/4 cups sugar, 2 tsp vanilla, and 3 eggs at medium speed until well combined.
3. On low speed, beat in the cooled chocolate mixture.
4. Beat in 1 cup all-purpose flour just until blended. Do not overmix.

**For the Cookie Dough:**

1. In a small bowl, mix together 1/4 cup unsalted butter, 1/4 cup light brown sugar, and 2 tbsp granulated sugar until smooth.
2. Add in the egg yolk and 1/2 tsp vanilla and mix until fully combined.
3. In a separate bowl, whisk together 0.5 cup + 1 tbsp all-purpose flour, 1/4 tsp baking soda, and 1/4 tsp salt.
4. Add the dry ingredients to the wet ingredients and mix until fully combined, then fold in 1/3 cup chocolate chips.

**Assembly and Baking:**

1. Pour the brownie mixture into your greased 12-inch cast iron skillet.
2. Take small chunks of the cookie dough and sprinkle them on top of the brownie batter.
3. Sprinkle approximately 10 tiny marshmallows on top of the cookie dough.
4. Bake for 30 minutes, or until a toothpick inserted into the center comes out clean.
5. Cool completely for about 1 hour before serving. Spoon ice cream of your choice on top of the warm brownie cookie skillet and enjoy!