Heat oven to 350°F. Spray bottom and sides of 13x9-inch pan with cooking spray. (I line my pan with foil then spray with cooking spray. This way it’s easier to get the brownies out of the pan and cut into squares)

In large bowl, stir cookie base ingredients until soft dough forms. Press dough in bottom of pan. Set aside.

In large bowl, beat cream cheese, granulated sugar, 1/4 cup butter, the flour, 1 teaspoon vanilla and the egg with electric mixer on medium speed until smooth. Stir in 1/4 cup pecans. Spread over cookie dough base. Sprinkle with chocolate chips.

Bake 26 to 28 minutes or until filling is set. Sprinkle evenly with marshmallows. Bake 2 minutes longer. Cool for 30 minutes on a cooling rack.

In 2-quart saucepan, melt 1/4 cup butter over medium heat. Stir in cocoa and milk. Heat until starts to thicken. Remove from heat. With wire whisk, gradually stir in powdered sugar until well blended. Stir in 1/2 teaspoon vanilla and 1/2 cup pecans. Immediately drizzle icing over brownies.

Refrigerate about 2 hours or until chilled. For bars, cut into 6 rows by 4 rows. Store covered in refrigerator.