Flaky Parmesan Crackers

Combine flour, Parmesan cheese, butter, salt, and mustard for dough in the bowl of a food processor; pulse until mixture is well combined and resembles bread crumbs. Pour 1/2 of the cream in slowly, with the processor running, until combined. Continue adding remaining cream, a little at a time, until dough has come together in clumps and feels like a damp, but not sticky, slightly over-processed pastry dough.

Gather dough into a ball, then roll into a log. Wrap in plastic and place in the refrigerator to chill for 30 minutes or longer.

Preheat the oven to 400 degrees F (200 degrees C).

Cut dough into quarters, then cut each quarter into 8 pieces. Lightly flour each piece as needed and feed through one of the thinnest settings of a pasta roller to make irregularly shaped, oblong crackers that are about 1/16 inch thick, 2 inches wide, and 8 inches long. Alternatively, use a rolling pin to roll dough out on a lightly floured countertop, and cut into any shape you wish.

Working in batches, lay crackers on a baking sheet. Brush with beaten egg and sprinkle with Parmesan.

Bake each batch in the preheated oven until crackers are browned at the edges, golden in the middle, and fully cooked through, 8 to 9 minutes. They will crisp as they cool.