Preheat oven to 350. Spray 9x13" pan with nonstick cooking spray.

In medium bowl, mix flour, baking powder, and salt.

In large mixing bowl, beat butter and sugar until light and fluffy.

Add eggs, one at a time, beating until blended. Add vanilla.

Gradually add flour mixture.

Add white chocolate chips.

Spread into prepared pan. Bake 26-30 minutes or until a toothpick inserted into the center comes out only slightly gooey. Don't over bake.