Got leftover corned beef from St. Patrick’s Day? Or maybe you made my Baked Corned Beef and Cabbage, and now you’ve got extra corned beef ready to be turned into something even better. Leftovers got a major upgrade with these corned beef sliders. Stacked with sweet caramelized onions, melty Swiss, and a buttery pickling spice glaze, these aren’t your average deli bites, they’re sweet, savory, toasty, and next-level.
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These are my go-to the day after St. Patrick’s Day, my kids devour them after school, and my husband sneaks extras when I’m not looking. This recipe just works.
Corned Beef Sliders at a Glance
- Total Time: 1 hour (35 min prep, 25 min bake)
- Make-ahead friendly: Prep up to 24 hours in advance or freeze baked sliders for later.
- Feeds: Makes 12 sliders, perfect for a family of four with a side or easily doubled for a crowd
- Dinner shortcut: Serve with kettle chips, fruit salad, or a quick slaw mix to round out the meal.
Ingredients You’ll Need
This sliders recipe is all about the balance—Hawaiian rolls bring sweetness, the corned beef adds salt and savor, and Swiss cheese melts perfectly over everything
For the Sliders:
- King’s Hawaiian rolls – These slightly sweet rolls are soft and pull-apart perfect. Their sweetness balances the salty corned beef like a dream.
- Corned beef – Use thin slices, either from leftovers or your local deli. It brings that classic briny, savory flavor we all love.
- Swiss cheese – Melts beautifully and adds a nutty, mild flavor that pairs perfectly with the beef. No Swiss? Try provolone, white cheddar, or mozzarella.
- Onions – Slowly caramelized until golden and sweet, they add a mellow richness that ties the whole slider together.
- Butter + brown sugar – Used to caramelize the onions and coax out every bit of natural sweetness.
For the Mustard Horseradish Sauce:
- Dijon mustard – Provides tanginess and depth.
- Prepared horseradish – Prepared horseradish is a pungent, spicy root condiment found near the mustard or refrigerated sauces at the grocery store. It’s got a nose-tingling heat but mellows when mixed with mayo and honey. If you’re unsure, start with just a little!
- Honey – Balances the heat from the horseradish and tanginess of the mustard.
- Mayonnaise – Creates a creamy, spreadable texture.
Not into horseradish? Sub in extra tablespoon of honey to make a plain honey mustard. Like heat? Get horseradish labeled hot.
For the Pickling Spice Butter Topping:
- Butter – Creates a gorgeous golden-brown top on the rolls.
- Worcestershire sauce – Adds umami and depth of flavor.
- Pickling spice – It’s a blend of whole spices, like mustard seeds, coriander, cloves, and bay leaf used in brines and slow cooking. You can find it in the spice aisle (near the jars of bay leaves and peppercorns), or use a homemade mix with mustard seeds, peppercorns, and a pinch of cinnamon or allspice. I chose this because it is the same seasoning that comes with fresh corned beef.
- Don’t want Pickling Spice? Try This Instead: If you don’t have pickling spice, try ½ teaspoon dried dill, celery seed, or even everything bagel seasoning. Want a Reuben twist? Add a pinch of caraway seeds!
- Garlic powder – For a touch of savory flavor.
Which Swiss? Choosing the Right Cheese for Your Sliders
Cheese Note:
I used imported Swiss (Emmental) for these sliders, sliced thin, because I’m not into overly cheesy bites. It’s a little bolder in flavor, melts like a dream, and the slices are longer and wider, so 6 slices were all I needed to cover the rolls.
If you’re using domestic Swiss, which is milder and comes in smaller slices, go with 12 slices to get full coverage and that perfect melty pull in every bite.
Let’s Make Corned Beef Sliders!
Caramelize the onions:
Melt butter in a large skillet over medium-low heat. Add the thinly sliced onions and sprinkle with a pinch of salt. Cook slowly, stirring occasionally, for about 30 minutes. This is not the time to rush! Low and slow is the secret to perfectly caramelized onions.
Once the onions are soft and golden brown, add the brown sugar, stir, and cook for another 5 minutes until they’re gorgeously caramelized. Set aside to cool slightly.
First time caramelizing onions? Keep the heat low and stir every 5–10 minutes. They should be soft, golden brown, and smell slightly sweet when they’re ready.
Pro tip: You can caramelize the onions up to 3 days ahead and store them in the refrigerator until ready to assemble the sliders!
Make the horseradish sauce
In a small bowl, add Dijon mustard, horseradish, honey, and mayonnaise.
Stir until well combined and set aside.
Mix the pickling spice butter
Combine melted butter, Worcestershire sauce, pickling spice, and garlic powder in a small bowl. Stir well and set aside.
Slice and prep the rolls
Using a large serrated knife, slice the entire package of Hawaiian rolls horizontally (don’t separate them yet!). Place the bottom on a baking sheet lined with parchment paper.
Layer the flavor
Spread a thin layer of mustard and horseradish sauce on the bottom half of the rolls.
Lay a layer of Swiss cheese covering the mustard and horseradish sauce.
Distribute the corned beef evenly over the cheese layer.
Spread the caramelized onions over the corned beef.
Add the remaining slices of Swiss cheese to cover the onions.
Add the tops and brush with butter
Place the top half of the rolls over everything.
Brush the pickling spice butter mixture generously over the tops of the rolls.
Bake to golden, melty perfection.
Cover loosely with foil and bake for 15 minutes. Remove the foil and bake for an additional 5-8 minutes until the tops are golden brown and the cheese is melted.
Recipe Variations
- Reuben-Style Sliders: Replace the onions with a layer of well-drained sauerkraut and substitute the mustard-horseradish sauce with Russian dressing.
- For extra picky eaters: skip the sauce and go simple: just beef and cheese between soft slider buns. You can add a side of salad dressing or Thousand Island dressing for dipping, fun and flavorful!
Storing & Reheating Tips
- Leftovers: Store any leftover sliders in an airtight container in the refrigerator for up to 3 days.
- Reheating: Wrap leftovers in foil and reheat in a 325°F oven for 10-15 minutes until warmed through.
- Air Fryer Reheat Tip: Pop leftover sliders into the air fryer at 320°F for 5–7 minutes. If they’re a little dry, brush a bit of melted butter on top before reheating.
- NOTE ON FREEZING: I haven’t tested freezing these yet, so I can’t say for sure. If you try it, please let me know! In our house, they’re gone too fast to freeze.
What to Serve With Sliders
These corned beef sliders are rich, savory, and melty, so pairing them with something crisp, fresh, or tangy helps round out the meal beautifully. Here are some easy ideas:
- Creamy Coleslaw – A cool, crunchy slaw balances the warm sliders. Try my Creamy Coleslaw with Celery Seed for a quick side.
- Kettle Chips or Pretzel Crisps – Add crunch without extra effort. Choose plain or salt and vinegar to cut through the richness.
- Fruit Salad – A colorful bowl of melon, grapes, and berries adds freshness and sweetness the kids will love.
- Dill Pickles – Tangy, sharp, and so satisfying with melty cheese and beef.
- Simple Green Salad – Keep it light with a vinaigrette or honey mustard dressing to complement the sliders.
Corned Beef Slider Questions, Answered
For these sliders, I use a creamy horseradish-Dijon mustard sauce, it’s tangy, a little spicy, and cuts through the richness like a charm. Not a horseradish fan? Try honey mustard, Thousand Island, or even Russian dressing for a more Reuben-style slider.
Line your baking sheet with parchment paper and don’t overload the filling. Baking uncovered helps the tops get golden and keeps the bottoms crisp. Want extra insurance? Toast just the bottoms of the rolls in the oven for a few minutes before assembling.
Swiss is the classic choice (especially imported Emmental for big flavor and meltability), but provolone, white cheddar, or mozzarella all work great too. Use what your family loves!
Dijon brings a smooth tang, but spicy brown mustard or classic yellow mustard will also work. If you like things sweet, go for honey mustard.
Corned Beef Sliders with Caramelized Onions
Equipment
- Large skillet
- Sheet pan
- Pastry brush or spoon
- Aluminum foil and parchment paper
Ingredients
- 1 package King's Hawaiian sweet rolls, 12 count
- 1 pound thinly sliced deli corned beef or leftover corned beef
- 12 slices Swiss cheese (about 8 oz or 1/2 lb.) *see note below
- 2 tablespoons butter
- 2 large onions thinly sliced
- 1 tablespoon brown sugar
- 1/2 teaspoon (2g) diamond crystal kosher salt (half if using table salt)
- 1/4 teaspoon black pepper (preferably freshly cracked)
Mustard Horseradish Sauce:
- 3 tablespoons Dijon mustard
- 2 tablespoons prepared horseradish, drained
- 1 tablespoon honey
- 1 tablespoon mayonnaise
For the Pickling Spice Butter Topping:
- 1/4 cup 4 tablespoons butter, melted
- 1 tablespoon pickling spice, coarsely ground *see note below
- 1 teaspoon Worcestershire sauce
- 1/2 teaspoon garlic powder
Instructions
- Prepare the caramelized onions: In a large skillet over medium-low heat, melt 2 tablespoons of butter.
- Add thinly sliced onions with a pinch of salt and cook slowly, stirring occasionally, for 30-35 minutes until golden brown. Add brown sugar, stir, and cook for another 5 minutes. Set aside.
- Make the mustard horseradish sauce: In a small bowl, combine Dijon mustard, horseradish, honey, and mayonnaise. Stir until well combined and set aside.
- Prepare the pickling spice butter topping: In a small bowl, combine melted butter, Worcestershire sauce, crushed pickling spices, and garlic powder. Stir well and set aside.
- Preheat oven to 350°F (175°C). Line a sheet pan with parchment paper.
- Without separating the rolls, slice the entire package of Hawaiian rolls horizontally in half. Place the bottom half in the prepared baking dish.
- Spread a thin layer of the mustard horseradish sauce on the bottom half of the rolls.
- Layer 6 slices of Swiss cheese on top of the sauce.
- Add a layer of corned beef, evenly distributing it across the rolls.
- Spread the caramelized onions evenly over the corned beef.
- Place the remaining 6 slices of Swiss cheese on top of the onions.
- Place the top half of the rolls over the cheese layer.
- Brush the pickling spice butter mixture generously over the tops of the rolls.
- Cover loosely with foil and bake for 15 minutes. , then remove the foil and bake for an additional 5-8 minutes until the tops are golden brown and the cheese is melted.
- Let cool for 5 minutes before slicing into individual sliders and serving.
Notes
- You can caramelize the onions up to 3 days ahead of time and store them in the refrigerator.
- *For the pickling spice, grind the spices using a coffee grinder and spice grinder, or a mortar and pestle.
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*Cheese Note:
I used imported Swiss (Emmental) for these sliders, sliced thin, because I’m not into overly cheesy bites. It’s a little bolder in flavor, melts like a dream, and the slices are longer and wider, so 6 slices were all I needed to cover the rolls. If you’re using domestic Swiss, which is milder and comes in smaller slices, go with 12 slices to get full coverage and that perfect melty pull in every bite.
