Mom's Homemade Scottish Shortbread

1 cup butter

1/4 tsp. salt

1/2 c. powdered sugar

2 cups unbleached all purpose flour

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Soften butter.  Add salt, sugar and flour and mix with fork until dough forms.  Press into  9x9 or round 9 inch cake pan and prick about every 1/2 inch with fork.  Place in preheated oven (425) for about 25-35 minutes (until slightly brown).  Let cool and enjoy.