2 c. plus 2 T. bleached, unsifted all-purpose flour
1/2 t. baking soda
1/2 t. salt
1 1/2 sticks (6 oz.) unsalted butter, melted and cooled to warm
1 c. packed brown sugar (light or dark, I prefer dark)
1/2 c. granulated sugar
2 t. vanilla
1 egg plus 1 egg yolk
1 c. (more if you prefer) chocolate chips (or hand cut chocolate into chip size)
Whisk together the flour, soda and salt in a medium bowl. Set aside.
With an electric mixer, beat the butter with the sugars. Add the vanilla and egg and yolk, mix until fully incorporated. Add the flour mixture, beat until just combined. Stir in the chocolate chips.
Refrigerate the dough for 24-36 hours.
Preheat oven to 325º. Adjust oven racks to upper and lower-middle positions. Form 2 inch balls and place on parchment or Silpat lined baking sheet, nine balls per sheet. Bake, reversing cookie sheets' positions halfway through baking, until cookies are light golden brown and outer edges start to harden yet centers are still soft and puffy, around 15 minutes. Let cool on sheet and then transfer to airtight container, if they're not already gone.