COMBINE flour, salt and cayenne pepper in food processor fitted with chopping blade. Cover and pulse a few times to blend ingredients. Add cheese and butter. Pulse until dough forms. Wrap dough in plastic wrap. Chill 30 minutes.
HEAT oven to 350°F. Divide dough in half. Roll out one half to 1/8-inch thickness on flat surface. Cut into 1-inch squares using a pizza cutter. Sprinkle lightly with kosher salt, if desired. Make a small hole in center of each cracker using a metal or wooden skewer. Place crackers on ungreased baking sheets using turner. Repeat with remaining dough.
BAKE 12 to 13 minutes or until crackers begin to turn light golden brown. Cool on baking sheet 3 minutes. Remove to wire rack to cool completely. Store in airtight container.
If you do not have a food processor, dough ingredients can be mixed by hand in large bowl, then kneaded on flat surface until well blended. Dough will be very stiff.