Mustard and pretzels make a crispy, salty breading for pounded pork tenderloin. These are a great game-day snack paired with a cold beer.
PREPARE THE BREADING: Stir the pretzel crumbs, flour, and 1 teaspoon salt together in a 9 by 13-inch baking dish. Whisk the eggs and mustard in a medium bowl.
MAKE A SAUCE: Combine the mayonnaise, chopped pickles, horseradish, and hot sauce in a small bowl.
BREAD THE PORK: Cut the pork tenderloin crosswise into 12 even pieces about 3/4 inch thick. Lay the pieces between sheets of plastic wrap and pound with a mallet until flattened into rounds roughly 2 1/2 inches in diameter and 1/4 inch thick. Press both sides of the pork into the pretzel flour, then dip each piece into the beaten eggs and again in the pretzel flour, until generously coated.
FRY THE PORK: Heat 1/4 inch of oil in a large skillet over medium-high heat until shimmering (about 375ºF). Line a plate with paper towels. Shallow-fry half of the pork cutlets until golden brown on each side, about 2 minutes per side. Transfer to the prepared plate to drain. Season generously with salt. Repeat with the remaining cutlets.
SERVE: Toast the rolls if desired and put a pork cutlet on each roll. Top each piece of pork with 1 rounded teaspoon sauce, 2 pickle slices, and a piece of lettuce.