Cream Butter and Sugars: In a small mixing bowl, combine the butter, granulated sugar, and brown sugar. Mix until smooth.
Add Wet Ingredients: Stir in the egg yolk and vanilla extract until fully blended.
Incorporate Dry Ingredients: Add the flour, baking soda, and salt to the bowl. Stir until the dough comes together.
Mix in Add-Ins: Gently fold in the chocolate chips and chopped nuts (if using).
Prepare for Baking: Butter a 10-ounce ramekin and press the cookie dough evenly into it. Alternatively, shape the dough into one large cookie and place it on a cookie sheet.
Bake: Place in the oven and bake for 22–25 minutes, or until the top is golden brown and the edges are set.
Cool: Remove the cookie from the oven and let it cool on a wire rack for 10 minutes before serving.
Video
Notes
Use Properly Softened Butter: The butter should be softened but still cool to the touch. It should leave an indentation when pressed with a finger.
Prepare the Ramekin: Lightly butter the ramekin to prevent sticking and make cleanup easier.
Choose the Right Ramekin: A 10-ounce ramekin works best for this recipe.