They're supposed to be big according to the original recipe but I like smaller cookies so I used a small cookie scoop. Don't be tempted to over-cook them. When you take them out they should look slightly undercooked, they'll finish cooking to chewy perfection on the baking sheet. The original recipe doesn't say this, but I chilled my dough for an hour. Chill between batches so it doesn't warm up.
Sorry, I don't remember how many cookies I got out of this recipe.
2 cups all-purpose flour
1/2 teaspoon baking soda
1/2 teaspoon salt
3/4 cup unsalted butter, melted
1 cup packed brown sugar
1/2 cup white sugar
1 tablespoon vanilla extract
1 egg yolk
1 cup semisweet chocolate chips
1 cup white chocolate chips
Preheat the oven to 325F and line cookie sheets with parchment paper.
Sift together the flour, baking soda and salt. Set aside.
In a medium bowl, cream together the melted butter and sugars for a minute until well combined. Beat in the vanilla, egg, and egg yolk until light and creamy, about 3 minutes.
Using a wooden spoon, mix in the dry ingredients just until combined, ten stir in the chocolate chips. Chill for at least an hour.
Drop cookie dough using a small cookie scoop (or teaspoon) onto the prepared sheets.
Bake for 6-8 minutes or until the edges are lightly golden. Cool on baking sheets for a few minutes before transferring to wire racks to cool completely.
Adapted from All Recipes.