Preheat oven to 325° Fahrenheit. Line a baking sheet with silicone mat or parchment.

In a large bowl, beat together butter and sugar until light and fully.

Add cornstarch and mix until fully combined.

Add Salt and All-Purpose Flour. Mix until fully combined.

Roll dough into a large ball. Press between two sheets of parchment paper or silicone mats to make the ball into a disk.

Using a rolling pin, spread the dough into a square that fits inside of the baking sheet.

With a roller cutter (if able, a knife will also work), Cut butter cookies into rectangles. Use a fork to create patterns.

Bake for 15-18 minutes or until the edges are just starting to brown. Remove from the oven and let cookies rest on baking sheet for 5 minutes until transferring to a cooling rack.

Optional. Sprinkle with powdered sugar to taste.