Preheat your oven to 350 degrees Fahrenheit. Line a 9 by 13 pan with parchment paper (see photo in the post), or spray lightly with cooking spray.
In a medium bowl, whisk the flour, baking powder, and salt.
1 1/2 cups all-purpose flour, 1 teaspoon baking powder, 1/2 teaspoon table salt
In the bowl of a stand mixer or in a large bowl with a hand mixer, cream together the brown sugar and butter, for about 3 minutes. Mix in the eggs one at a time until they are incorporated. Then add in the vanilla extract.
1 1/2 cups packed light brown sugar, 12 tablespoons unsalted butter, 2 large eggs, 2 teaspoons vanilla extract
Add in the flour mixture. Turn the mixer on low and mix until it is just combined enough that you can turn it all the way up to finish incorporating the flour mixture. Mix until it is just incorporated, being careful not to overmix.
Mix in the white chocolate chips. Then spread the dough in the prepared baking dish.
1 cup white chocolate chips
Bake for 20 to 25 minutes. Allow to cool before slicing. Enjoy!