Step 1

Preheat the oven to 350 degrees.

Step 2

Mix butter, sugars, vanilla, and egg yolk until combined.

Step 3

Stir in flour, cornstarch, baking soda, and salt. When a soft dough has formed, stir in the chocolate chips.

Step 4

Roll the dough into two balls and place on a baking sheet – there should be plenty for two large cookies plus a little bit of dough for a snack. (You’re welcome.) You can add more chocolate chips to the top of the cookies if you want.

Step 5

Bake for 10-12 minutes, depending on your oven temp and desired level of gooey cookie center.

Step 6

Rest the cookies for a few minutes so they settle down and solidify a bit –  I set a timer for 10-15 minutes and just let them rest right on the pan. At that point they should be able to transfer to a plate, or maybe even held in your hand, for warm, delicious eating on the couch. Yum, yum, yum.