Step 1

Heat oven to 350°F. Line 8-inch square pan with foil; spray with cooking spray.

Step 2

In medium bowl, mix cookie mix, butter and egg until soft dough forms. Stir in oats until blended. Remove 2/3 cup of the cookie dough; set aside. Press remaining dough evenly in bottom of pan.

Step 3

In 1-quart saucepan, heat chocolate chips, condensed milk and peanut butter over low heat 2 to 3 minutes, stirring frequently, until chocolate is melted and mixture is smooth and slightly thickened. Spread mixture on top of cookie base. Break remaining cookie dough into small pieces; sprinkle over top.

Step 4

Bake 25 to 30 minutes or until cookie dough is golden brown. Cool completely, about 2 hours.

Step 5

Use foil to remove bars from pan. Cut into 4 rows by 4 rows. Store covered in airtight container at room temperature.