Preheat the oven to 325F degrees. Line a cookie sheet with grease or parchment Set aside.
In a medium-sized bowl, sift together the flour, baking soda, and salt. Set aside.
2 cups all-purpose flour, 1/2 teaspoon baking soda, 1/2 teaspoon salt
In a medium bowl using a hand mixer or a stand mixer with a paddle attachment, cream together the melted butter, brown sugar, and white sugar until creamy and smooth. Add in the vanilla, egg, and egg yolk until light and creamy. Slowly add in the sifted ingredients and mix until combined. Stir in the chocolate chips by hand using a wooden spoon.
3/4 cup unsalted butter, 1 cup brown sugar, 1/2 cup white sugar, 1 Tablespoon vanilla extract, 1 large egg, 1 egg yolk, 2 cups semisweet chocolate chips
Form cookie dough into balls roughly 1 teaspoon in size or use a cookie dough scoop. Cookies should be about 3 inches apart on the cookie sheet.
Bake for 15 to 17 minutes in the preheated oven, or until the edges are lightly toasted. Cool on baking sheets for a few minutes before transferring to wire racks to cool completely.