Preheat oven to 325 degrees F. In a bowl, mix together flour, baking soda and salt, then set aside.

In another bowl, whisk the cooled butter and sugars until they are combined. Add the egg, egg yolk, and vanilla and stir until mixed and smooth. Gradually add in dry ingredients and mix with a spoon until a dough forms – it will look crumbly at first, but it will come together. I even used my hands to help at one point. Fold in all of your add-in’s here, using a spoon and also your hands to bring it together. I literally smashed the ingredients into the dough.

Roll dough into 1 1/2-inch balls and place on a nonstick baking sheet (I actually used this method of stacking the dough) about 2 inches apart. Bake for 9-12 minutes, or until the middles are just set. Don’t over bake! Let cool almost completely.