Step 1

Set oven to 350F. Line an 9x9 inch baking sheet with parchment paper and melt the butter you'll need for the recipe in a large bowl.

Step 2

Add the flour, salt, baking soda, and corn starch to a medium bowl then whisk together and set aside.

Step 3

Pour the melted butter into a large bowl. Add the white and brown sugars and whisk together, they'll form a somewhat thick slurry.

Step 4

Add the eggs and vanilla to the butter mixture and mix together well.

Step 5

Dump the dry mixture into the wet and mix until almost combined then stir in all but a handful of the white chocolate chips, mixing so they're distributed.

Step 6

Transfer the dough to an 9x9 inch baking dish lined with parchment paper and spread toward the edges giving it a rough smooth. Top with the reserved white chocolate chips.

Step 7

Bake for about 35 minutes at 350F. The cookie bars are done when the edges are set and golden brown and a toothpick or skewer inserted into the center comes out mostly clean. Let the cookie bars cool in the pan for about an hour before removing and cutting.