Corned Beef Sliders Mustard

The smell of butter and poppy seeds hitting a hot oven takes me back to my cousin's Super Bowl parties, where these sliders would disappear faster than we could plate them. I've since learned that the magic lies in that butter brush getting into every crevice of the bun. Something about how the Swiss melts into the corned beef while the tops turn golden makes people hover around the baking sheet like it's the most fascinating thing they've ever seen.

Last winter my neighbor knocked on my door holding a container of leftover corned beef from St. Patrick's Day, looking completely lost about what to do with it all. We spent the afternoon experimenting with sandwich combinations, and this slider version was the undeniable winner. Now I keep poppy seeds in my pantry just for moments like that—when good food calls for improvisation and someone shows up with perfect timing.

Ingredients

• Sliced corned beef: Ask your deli counter for thin slices, they melt better against the cheese than thick cuts do
• Slider buns: Softness matters here—avoid artisan rolls that might overpower the delicate fillings
• Swiss cheese: The nutty flavor bridges the sharp mustard and salty beef perfectly
• Whole-grain mustard: Provides texture and tang that cuts through all that richness
• Red onion: Thin slices add just enough bite without overwhelming the other flavors
• Dill pickle: One slice per slider delivers that classic deli combination we all secretly love
• Butter mixture: This is what transforms good sliders into something people talk about later

Instructions

Get your oven ready:

Preheat to 180°C (350°F) and line a baking sheet with parchment paper for easy cleanup later

Prep the bun bottoms:

Slice each slider bun in half and arrange the bottom halves on your prepared baking sheet like little soldiers

Build the layers:

Stack corned beef, Swiss cheese halves, onion rings, and one pickle slice onto each bun bottom with steady hands

Season the tops:

Spread whole-grain mustard (and mayonnaise if you're feeling indulgent) on the inside of each top bun

Assemble and brush:

Place tops on sliders, then whisk melted butter with Dijon mustard, garlic powder, and poppy seeds before brushing generously over every bun

Bake to golden:

Cover loosely with foil and bake for 10 minutes, then remove foil for 5 more minutes until cheese melts and tops turn irresistible

Save

My teenage son started requesting these for every gathering after he accidentally served them at a study session and his friends wouldn't stop texting him for the recipe. Now making sliders has become our pre-party ritual, him brushing the butter while I layer the ingredients, both of us knowing these tiny sandwiches will be gone before anyone even says grace.

Make-Ahead Magic

You can assemble these sliders hours before baking, just wrap the tray tightly and refrigerate until 20 minutes before you need them. The buns actually benefit from sitting briefly with the fillings.

Bread Wisdom

Rye buns elevate these sliders to deli status, but Hawaiian sweet rolls create an entirely different experience with their subtle sweetness balancing the savory beef. Trust your mood.

Serving Strategy

These sliders reheat surprisingly well in a low oven if you have leftovers, which rarely happens but good to know. I've also made them with leftover brisket when corned beef wasn't available and nobody complained.

• Have extra mustard on the table for the mustard lovers
• Pair with something cold and crisp
• Consider making a double batch immediately

Save

There's something impossibly satisfying about handing someone a warm slider, the butter still glistening on top, and watching their face light up. These little sandwiches have a way of making any gathering feel like a celebration.

Recipe FAQs

→ What type of cheese works best for these sliders?

Swiss cheese is ideal for its mild, nutty flavor and excellent melting properties, complementing the savory corned beef.

→ Can I prepare these sliders ahead of time?

Yes, you can assemble the sliders and refrigerate them covered before baking. Bake just before serving for best texture and warmth.

→ What alternative buns can I use?

Mini rye buns add a classic deli touch, while soft slider buns provide a tender, pillowy base for the fillings.

→ How do I make the topping golden and flavorful?

Brush the tops with a mix of melted butter, Dijon mustard, garlic powder, and optional poppy seeds, then bake to achieve a golden crust.

→ Are there any suggested beverage pairings?

These sliders pair well with a crisp lager or a light-bodied red wine, enhancing the savory flavors.