Melt butter in heavy 2-quart saucepan over medium-high heat; watch closely. Simmer butter for about 5 minutes or until it foams and turns deep golden brown. Immediately remove from heat and pour into a medium size bowl. Refrigerate 15 minutes.

Pre-heat oven to 375°F. Line a 13x9-inch baking pan with aluminum foil, extending foil over the edges of your pan. Spray the bottom of the pan with non-stick cooking spray and set aside.

Remove butter from refrigerator and add brown sugar, eggs and vanilla to bowl and mix well. Combine flour, baking powder and salt and add to butter mixture; stir just until combined. Stir in pecans and white chocolate chips and spread mixture into prepared pan.

Bake 18-22 minutes or until golden brown around edges and toothpick inserted in center comes out clean. Cool completely.

Use foil 'handles' to remove the blondies from the pan and cut into squares for serving.