Peanut Butter Brownie Squares

In the bag:
1 pkg Chewy Fudge Brownie Mix
1 ½ c. powdered sugar
1/3 c. peanut butter
1/3 c. chocolate chips
1 T. shortening

From the kitchen:
eggs, oil & water for brownie mix
¼ c. plus 2 T. milk
2 T. butter

Directions:
1. Preheat oven to 350 degrees. Grease bottom only of 13x9x2-inch pan.
2. Prepare and bake brownies following package directions for high-altitude, cake-like brownies. Cool 5 to 10 minutes.
3. For frosting, combine powdered sugar, peanut butter, milk and butter in small bowl. Beat at medium speed with electric mixer until blended. Spread over warm brownies.
4. For drizzle, microwave baggie with chocolate chips and shortening at high power for 1 minute or until melted. Snip pinpoint hole in bottom corner of bag. Drizzle over frosting. Allow chocolate to set before cutting into bars.