Found a recipe forum entry claiming this was from an old Seventeen. Not sure if this is the November 1982 version. If anyone has the page, please share!
Seventeen Shortbread (we think)
1 cup unsalted butter, softened
1⁄2 cup sugar
2 cups all-purpose flour, unsifted
Preheat oven to 300 degrees Fahrenheit.
Beat butter and sugar until creamy and fluffy.
Gradually add in flour until thoroughly mixed.
Spread or pat evenly in ungreased 13×9 pan or on an ungreased cookie sheet.
Bake for 30-40 minutes or until lightly browned.
Immediately after removing from oven, prick all over with fork, then cut into bars.
Cool completely before removing from pan.
Here is a crappy copy of the nacho casserole recipe. If you have an original page, please share!