Mix the butter, blue cheese, flour, and salt in a food processor, and process until smooth. Transfer to a bowl, and stir in the walnuts. Cover, and chill 5 minutes in the refrigerator.
Divide dough in half. Form each half into a log shape. Wrap in plastic wrap, and refrigerate 1 hour, until firm.
Preheat oven to 350 degrees F (175 degrees C). Slice the dough logs into 1/4 inch rounds, and arrange rounds on a baking sheet.
Bake 12 minutes in the preheated oven.