Step 1

In a medium mixing bowl, sift together your flour, baking soda, baking powder, salt and cornstarch.

Step 2

Using a stand mixer or a hand mixer, whisk the cold butter until fluffy (this should take about 3-4 minutes.

Step 3

Add both sugars to the butter and whisk until it is combined.

Step 4

Add your eggs one at a time to the creamed butter, whisking before you add the next egg.

Step 5

Next, add your vanilla and mix until incorporated.

Step 6

In 1 cup increments, pour your dry ingredients into the butter mixture. Stop when everything is just combined and it becomes dough-like. Be careful not to over-mix as that can create a tough cookie.

Step 7

Add your chocolate chips and chocolate chunks to the dough and fold them in.

Step 8

Scoop out the dough and roll them into 5-ounce balls. Place the balls on a baking sheet topped with parchment paper and refrigerate for at least 1 hour. Refrigerating them overnight is ideal.

Step 9

Once the cookie dough is chilled transfer them straight into a preheated oven set to 375°F. Bake them for 14 minutes rotating the baking sheet halfway through baking time. For the last 4-5 minutes bake the cookies at 400°F so that the outside of the cookie can develop a more golden color and become crunchier.

Step 10

Take the cookies out of the oven and let them sit on the baking sheet for at least 10 minutes, (they will continue to bake as they cool), before enjoying.