Triple Chocolate Cookie Bars

I found these bars online, but the page no longer exists. I had to pat the thick dough into the pan and spread it out. Sabrina said they taste like fudge bars. Simple and chocolatey! 

Triple Chocolate Cookie Bars

2 c. flour
1/2 c. unsweetened cocoa powder (Special Dark recommended)
1/2 t. baking soda
1/4 t. salt
3/4 c.granulated sugar
1/2 c. brown sugar, firmly packed
3/4 c. butter, at room temperature
2 eggs
1 1/2 c. white chocolate chips

Topping:
1 1/2 c. semisweet chocolate chips

     Preheat the oven to 350º. Line a 9 x 13-inch baking pan with non-stick foil.

     Lightly spoon flour into measuring cup and level off with the flat backside of a butter knife. In a medium bowl, whisk together flour, cocoa, baking soda, and salt. Set aside.

     In a large bowl, cream together white sugar, brown sugar, and butter until light and fluffy. Add eggs and mix until combined. Add flour mixture and beat until combined. Mixture will be very thick. Stir in white chocolate chips. Pour batter into prepared baking pan, smoothing evenly to a uniform depth. Bake 20 to 25 minutes until toothpick inserted in the center comes out almost clean. Do not over-bake.

     Spread semisweet chocolate chips evenly on top of hot cookie bars. Cover loosely with foil and let rest 5 minutes to let chocolate chips soften. Remove foil and spread soft chocolate with a spatula to frost cookie bars. Let rest about 4 hours or overnight at room temperature for topping to set.

Using the foil, lift the bar cookies out of the pan. Peel down the foil and cut into bars to serve.