Preheat the oven to 350 degrees F.
In the bowl of an electric stand mixer or in the food processor fitted with a steel blade, place shredded cheese and softened butter.
Beat or process until well combined. Add flour, cayenne pepper and pecans. Beat or process a bit more, or until pecans have just been incorporated.
Shape the dough into four logs, about 1 1/4 inches in diameter. Wrap in plastic wrap or waxed paper and chill 1 hour, or freeze for about 20 minutes.
** Slice logs into 1 /4 -inch rounds and bake in batches on ungreased baking sheets until crisp but not browned, 12-15 minutes.
With a metal spatula, remove the crackers to a wire rack to cool. Serve at once or store in an airtight container for up to a week.
*NOTE: The dough may appear dry, so more butter may be needed.
**This dough may be frozen, baked or unbaked, for up to 6 months.