How to Make It
Whisk together flour, salt, and baking soda in a medium bowl. Combine brown sugar, butter, and granulated sugar in the bowl of a heavy-duty electric stand mixture; beat on medium speed until creamy, about 3 minutes. Add peanut butter, egg, and vanilla; beat until smooth. Gradually add flour mixture; beat until smooth. Stir in chocolate chips, pretzels, chocolate sandwich cookies, 1 cup of the potato chips, and 1/3 cup of the candy-coated chocolate pieces.
Press dough evenly into a lightly greased 13- x 9-inch rimmed baking sheet. Top evenly with remaining 1/4 cup potato chips and 2 tablespoons candy-coated chocolate pieces. Bake in preheated oven until light golden brown, 20 to 23 minutes. Let stand at least 20 minutes before cutting into bars.