Ingredients:

  • 1 cup (2 sticks) unsalted butter, softened
  • 1 cup packed light brown sugar
  • 1/2 cup granulated sugar
  • 2 large eggs, room temperature
  • 2 teaspoons vanilla extract
  • 2 1/4 cups all-purpose flour
  • 3/4 cup high-quality unsweetened cocoa powder (Dutch-process recommended)
  • 1 teaspoon baking soda
  • 1/2 teaspoon fine sea salt
  • 1 cup dark chocolate chips or chunks (60-70% Cacao), plus extra for topping
  • 1 1/2 cups mini marshmallows (Optional for swirl)

Instructions:

  1. Whisk the flour, cocoa powder, baking soda, and salt together in a medium bowl. Set aside.
  2. In a stand mixer, cream the softened butter, brown sugar, and granulated sugar until light and fluffy (about 3 minutes). Scrape down the sides of the bowl.
  3. Beat in the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.
  4. Gradually add the dry mixture to the wet mixture on low speed. Mix just until combined—do not overmix.
  5. Gently fold in the chocolate chips/chunks using a rubber spatula.
  6. Cover the bowl and refrigerate the dough for a minimum of 45 minutes to prevent excessive spreading.
  7. Preheat oven to 350°F (175°C). Line two large baking sheets with parchment paper or silicone mats.
  8. Scoop rounded balls of dough onto the sheets, leaving 2 inches between them. Press a few extra chocolate chunks onto the top of each ball.
  9. If using, gently press 4-5 mini marshmallows onto the top centre of each dough ball.
  10. Bake for 10-12 minutes. Cookies should look set on the edges but still slightly soft/underbaked in the very centre.
  11. Let cookies rest on the hot baking sheet for 5 minutes before carefully transferring them to a wire rack to cool completely.