Slow-Cooker Mississippi Pot Roast Sandwich Recipe

In this Mississippi Pot Roast Sandwich, a lightly toasted sandwich roll is spread with roasted garlic aioli and layered with leftover pot roast, crispy fried onions, melty provolone cheese and sliced pepperoncini, then served with a simple au jus for dipping. Recipe yields one sandwich and can be scaled up as needed.

I may or may not make Mississippi pot roast just so I can have this sandwich.

While the pot roast is delicious over mashed potatoes, I prefer it piled into a toasted sub roll with provolone. For this version I spread roasted garlic aioli on the roll, add warm shredded pot roast, top with crispy fried onions and provolone, broil until the cheese melts, and finish with pepperoncini and a side of au jus.

Serve with a bowl of au jus for dipping — it transforms the sandwich into something you’ll crave.

Ingredients

• 6-inch soft Italian roll or sub bun (French roll works too)
• Roasted garlic aioli — adds creamy, mellow garlic flavor
• Leftover Mississippi pot roast — about 3 to 4 ounces per sandwich
• Crispy fried onions — for crunch and caramelized onion flavor
• Provolone cheese — 2 slices, to melt over the roast
• Sliced pepperoncini peppers — about 2 tablespoons, or to taste
• Au jus — for serving and dipping

Quick Method

Preheat the broiler to high. Slice the sandwich roll and place it cut-side up on a rimmed baking sheet. Toast on the middle rack for 1 to 2 minutes until lightly golden. Remove and spread 2 tablespoons of roasted garlic aioli on the cut side.

Top the aioli with warm shredded Mississippi pot roast (about 3–4 ounces), then sprinkle on a generous handful of crispy fried onions. Add two slices of provolone and return the sandwich to the broiler just until the cheese melts, about 1–2 minutes.

Finish with sliced pepperoncini to brighten the flavors and serve immediately with au jus for dipping.

How to Make Roasted Garlic Aioli

Roast a head of garlic until soft and caramelized, allow it to cool, then squeeze the cloves into 1/2 to 3/4 cup mayonnaise and stir to combine. Store any leftovers in an airtight container in the refrigerator for up to two weeks.

How to Make Crispy Fried Onions

Thinly slice one medium to large yellow onion. In a 10-inch skillet, melt 2 tablespoons butter over medium heat. Add the sliced onions and a pinch of salt, then cook, stirring often, until the onions are deeply golden brown and crispy. This yields enough for 2–4 sandwiches depending on onion size.

Assemble and Serve

1. Toast the roll under the broiler until lightly golden.
2. Spread roasted garlic aioli on the toasted roll.
3. Add warm shredded pot roast, crispy fried onions and provolone; broil until cheese melts.
4. Top with sliced pepperoncini and serve with au jus for dipping.

Side Suggestions

• Au jus for dipping
• French fries (air-fryer or oven-baked)
• Sweet potato fries
• Onion rings
• Potato chips or potato wedges

This sandwich is simple but crave-worthy. The garlicky aioli, tender pot roast, crunchy onions and tangy pepperoncini create a perfect balance — and a quick au jus turns each bite into pure comfort.

Enjoy!