Tool

• 9‑inch round cake pan

• Whisk

• Piping bag with tip (or plastic sandwich bag)

Ingredients

For the cookie

• 1¾ cups all‑purpose flour

• ¾ teaspoon baking soda

• ½ teaspoon salt

• ½ cup unsalted butter, softened

• ¾ cup packed light or dark brown sugar

• ¼ cup granulated sugar

• 1 large egg, room temperature

• 2½ teaspoons vanilla extract

• 1½ cups semi‑sweet chocolate chips, plus more for sprinkling

For the frosting

• 6 tablespoons unsalted butter, softened

• 1¼ cups powdered sugar, sifted

• 3 tablespoons cocoa powder, sifted

• 2 tablespoons milk

• ½ teaspoon vanilla extract

• Sprinkles

Direction

For the cookie

• Preheat oven to 350°F. Grease a 9‑inch round cake pan.

• Sift flour, baking soda, and salt; set aside.

• Beat butter until smooth.

• Add brown sugar and granulated sugar; beat 2 minutes until smooth (not fluffy).

• Add egg and vanilla; mix well, scraping bowl as needed.

• Add flour mixture on low speed; mix just until combined.

• Fold in chocolate chips with a spatula.

• Press dough evenly into prepared pan; sprinkle extra chips on top.

• Bake 20–25 minutes until lightly browned and dry on the surface.

• Cool completely in the pan on a wire rack.

For the chocolate frosting

• Beat butter until smooth.

• Add powdered sugar, cocoa powder, milk, and vanilla; beat on low until combined.

• Increase speed to medium; beat 2 minutes until light and fluffy.

• Transfer frosting to a piping bag with decorative tip.

Assembly

• Remove cooled cookie from pan and place on a serving plate.

• Pipe frosting around the edge.

• Add sprinkles if desired.

Notes

• Pull the cookie once lightly browned — it continues cooking from residual heat.

• Let it cool fully in the pan before removing to avoid breaking.

Nutrition

Calories: 673kcal Carbohydrates: 86g Protein: 6g Fat: 34g Saturated Fat: 21g Polyunsaturated Fat: 1g Monounsaturated Fat: 9g Trans Fat: 1g Cholesterol: 79mg Sodium: 272mg Potassium: 299mg Fiber: 4g Sugar: 59g Vitamin A: 674IU Calcium: 59mg Iron: 4mg