The St. Louis pork tenderloin sandwich is a Midwestern classic: a pounded-thin, breaded, and fried pork cutlet served on a sturdy bun with pickles, onion, and mustard. It is a beloved regional specialty, often served at diners and taverns, and this recipe delivers the same crisp, juicy result at home. The key is pounding the meat thin for maximum crispy surface area and a quick, even cook.
Ingredients
- 1 lb (450 g) pork tenderloin, silver skin removed
- 1 cup (240 ml) buttermilk
- 1 large egg
- 1 cup (125 g) all-purpose flour
- 1 ½ cups (75 g) plain breadcrumbs (or panko for extra crunch)
- 1 tsp (5 g) garlic powder
- 1 tsp (5 g) onion powder
- 1 tsp (2 g) smoked paprika
- 1 tsp (5 g) salt, plus more for seasoning
- ½ tsp (1 g) black pepper
- Vegetable or canola oil, for frying (about 2 cups / 480 ml)
- 4 sturdy sandwich buns (such as Kaiser rolls or brioche)
- Dill pickle slices, for serving
- Thinly sliced red or white onion, for serving
- Yellow mustard, for serving
Instructions
- Slice the pork tenderloin crosswise into 4 equal pieces, about 1 inch (2.5 cm) thick. Place each piece between two sheets of plastic wrap and pound with a meat mallet or rolling pin until about ¼ inch (6 mm) thick. The cutlets will be large and irregular—that is perfect.
- In a shallow bowl, whisk together the buttermilk and egg. In a separate shallow dish, combine the flour, breadcrumbs, garlic powder, onion powder, smoked paprika, 1 tsp salt, and black pepper. Mix well.
- Dip each pork cutlet into the buttermilk mixture, letting the excess drip off, then press it firmly into the breadcrumb mixture, coating both sides completely. Place the breaded cutlets on a wire rack and let them rest for 10 minutes while you heat the oil.
- Pour the oil into a large, heavy skillet (cast iron works great) to a depth of about ½ inch (1.25 cm). Heat over medium-high until the oil shimmers and a pinch of breadcrumbs sizzles immediately when dropped in (about 350°F / 175°C).
- Working in batches if needed, carefully lay the cutlets in the hot oil. Fry for 2–3 minutes per side, until golden brown and crispy. The pork is done when it reaches a safe minimum internal temperature of 145°F (63°C) as measured with a food thermometer. Transfer to a paper-towel-lined plate and season immediately with a pinch of salt.
- Toast the buns lightly in the skillet or under a broiler for 1–2 minutes, until warm and slightly crisp.
- Assemble the sandwiches: spread mustard on the bottom bun, add the crispy pork cutlet, then top with pickle slices and onion. Cover with the top bun and serve hot.
Tips
- Pound evenly: The cutlets should be uniform in thickness so they cook evenly. If the edges are thinner, they will crisp faster—watch them closely.
- Don’t skip the rest: Letting the breaded cutlets rest before frying helps the coating adhere and prevents it from falling off in the oil.
- Oil temperature matters: If the oil is too hot, the coating burns before the pork cooks; if too cool, the cutlets absorb oil and turn greasy. Use a thermometer if you have one.
- Substitutions: No buttermilk? Use ¾ cup (180 ml) milk mixed with 1 tbsp (15 ml) lemon juice, let sit 5 minutes. Panko breadcrumbs give a lighter, crunchier crust than traditional breadcrumbs.
Serving Suggestions
Serve these sandwiches with classic sides like french fries, coleslaw, or a simple green salad. For a true St. Louis experience, pair with a cold beer (for adults of legal drinking age, please drink responsibly) or a tall glass of iced tea. Add extra pickles on the side—they cut through the richness perfectly.
Variations
- Spicy version: Add ½ tsp cayenne pepper to the breadcrumb mixture and use spicy brown mustard instead of yellow.
- Cheesy twist: Place a slice of American or provolone cheese on the hot cutlet right after frying so it melts slightly.
- Air fryer method: Lightly spray the breaded cutlets with oil and air fry at 400°F (200°C) for 10–12 minutes, flipping halfway, until golden and cooked to 145°F (63°C).
- Pork cutlet alternative: If you can’t find tenderloin, use boneless pork chops pounded thin—just trim excess fat.
Storage and Reheating
Store leftover fried cutlets (without buns) in an airtight container in the refrigerator for up to 3 days. To reheat, place them on a baking sheet in a 375°F (190°C) oven for 8–10 minutes, or until hot and crisp. Avoid the microwave, as it will make the coating soggy. Assemble sandwiches fresh with warm buns and cold toppings. Do not freeze fried cutlets—the coating will become mushy upon thawing.
Frequently Asked Questions
Can I use pork loin instead of tenderloin? Yes, pork loin works but is leaner and can dry out more easily. Pound it thin and be careful not to overcook; the 145°F (63°C) target with a 3-minute rest is essential.
Why is my breading falling off? Usually it’s because the cutlets weren’t dried before breading, or the oil wasn’t hot enough. Pat the pork dry with paper towels before dipping, and ensure the oil is at the right temperature before frying.
Can I make these ahead of time? You can bread the cutlets up to 4 hours ahead and keep them refrigerated on a rack. Fry them just before serving for the best texture.
What is the traditional St. Louis bun? Many local spots use a simple white hamburger bun, but a Kaiser roll or brioche holds up better with the large cutlet. Use whatever sturdy bun you prefer.
Is this the same as a Hoosier tenderloin sandwich? They are very similar, but Indiana’s version is often even larger and may be served with lettuce and tomato. St. Louis style typically keeps it simpler with pickle, onion, and mustard.
Can I bake these instead of frying? Yes, bake at 425°F (220°C) on a wire rack over a baking sheet for 15–18 minutes, flipping once, until golden and cooked through. They will be less crispy but still delicious.
Related
- Breaded Pork Tenderloin Sandwich Recipe
- How to Serve Stuffed Clams: A Step-by-Step Guide
- Salt Potatoes from Scratch: Step-by-Step Guide
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Safety notes: safe minimum internal temperatures from USDA FSIS; raw and undercooked fish guidance from the U.S. FDA. Food safety notes
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