In a bowl, whisk together salt, dry mustard, and cayenne pepper and set aside.
Mix cheese and butter with a stand or hand mixture until smooth.
Whisk the spice mix into the flour.
Add flour/spice mixture 1/2 cup at a time.
Knead the dough for a few minutes until all the little pieces that were at the bottom of the mixing bowl come together.
Roll dough into small balls, place them on a baking sheet covered with parchment or a non-stick baking pad.
Press each small ball with a small glass or a shot glass to flatten and make a consistent size.
Chill to dough balls for 1-2 hours.
Preheat oven to 350°.
Bake for 16-19 minutes until they are golden brown.
Cool for 10 minutes before serving.