Comforting Roast Beef Sliders

I love making these roast beef sliders loaded with sweet onions. You just can’t go wrong—savory beef, gooey cheese, and golden buns soaked in garlic butter? Friends grab them so fast, there’s never any left. Bonus: you won’t spend forever in the kitchen, either.

I actually whipped these up for a Super Bowl crowd once, totally last second because I was pressed for time. Everybody ate them up and now it's everyone's top pick for hangouts, no matter what we’re celebrating.

Tasty Ingredients

• Slider rolls: King’s Hawaiian buns are great since the hint of sweetness goes well with all the fillings
• Deli roast beef: ask for those thin slices—they make the bites super tender
• White cheese: Havarti, Swiss, or provolone all melt nicely without stealing the show
• Onions, large: Go with yellow—they cook down sweet and flavorful
• Butter: Needed both for frying up those onions and for the yummy garlic mix
• Garlic: Use both minced and powdered for layers of garlicky taste
• Rosemary: Adding this gives the onions a cozy, earthy kick
• Mustard powder: Just a teensy bit does the trick for extra depth

Simple How-To

Let Them Rest:

Once you pull the sliders out, set them aside for two or three minutes. That way, the cheese won’t ooze everywhere when you pick them up, and everything sets beautifully.

Bake Everything:

Slide your tray into the hot oven, bake for roughly 5 to 8 minutes. Keep an eye out so the cheese melts and the buns top turns perfectly golden but doesn’t turn hard.

Brush On Butter:

Take your garlic butter and slather it all over the buns—don’t forget the sides! This makes sure you get that flavorful goodness and crispy finish.

Mix Garlic Butter:

Stir melted butter, parsley, mustard powder, and garlic powder in a bowl till it looks smooth and smells great. This gets brushed on the buns soon.

Stack It Up:

Pile the roast beef onto the bottom half of your rolls, add a cheese blanket on top, then finish with a spoonful of caramelized onions for that hit of sweetness.

Prep Those Buns:

Place rolls onto a parchment-lined pan, slice across to open but keep tops and bottoms attached, and lift the tops off for now while you add the fillings.

Add Garlic and Herbs:

Throw the chopped rosemary and garlic into the pan when the onions start browning. Keep them moving for about five more minutes till everything smells incredible and the onions are jammy and dark gold.

Cook The Onions:

Put 3 tablespoons of butter in a big skillet on medium. Once melted and a little bubbly, toss in your onions. Turn the heat down and stir for 10–12 minutes, letting them break down slowly and get that sweet golden color.

Oven Ready:

Flip your oven on to 350°F and line up your parchment baking sheet—makes cleanup a breeze.

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Honestly, the onions are my favorite. Don’t rush ‘em—low and slow gives the best sweet flavor. The first time I made these, I hurried the onions and missed out. Now, I make more just to have on hand for sandwiches and salads all week.

Prep Ahead Tricks

So handy: you can cook the onions two or even three days before. Keep them in a sealed container in the fridge. The garlic butter is easy to prep a day in advance too—just pop it back in the microwave so it spreads nicely. Go ahead and build your whole tray during the day, cover it up, and chill it in the fridge until you’re ready to bake. If they’re cold, just give them a little more oven time.

Tasty Matches

Honestly, these are awesome alone, but a few sides turn them into a full meal. Chips or fries are always a win for casual parties. To lighten things up, add a fresh salad or a tart slaw for some crunch. Serving them as a starter? Toss in some pickles or spicy veggies to balance out all the richness.

Ways To Change It Up

Want to shake things up? Spread some horseradish sauce or creamy mayo on the buns for extra punch. Add crispy fried onions on top for crunch. Heat fans—tuck in jalapeño slices or splash hot sauce right into the butter. In the fall, a few thin apple slices between layers are sweet and surprising.

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Recipe FAQs

→ Can I choose a different kind of bread for these sliders?

Absolutely! If you don’t have slider buns or Hawaiian rolls, small bread rolls or mini sandwich buns can work too. Just make sure they’re sturdy enough for baking.

→ What’s a good cheese to put in these sliders?

Great options include Swiss, Havarti, or Provolone because they melt nicely without overpowering. Go ahead and pick a cheese you love most!

→ What’s the secret to perfect caramelized onions?

Cook sliced onions low and slow in some butter over medium heat. Stir them now and then, and toss in garlic and rosemary toward the end for extra flavor without burning the herbs.

→ Can these sliders be made ahead of time?

Definitely! Put everything together a few hours ahead (skip brushing on the garlic butter), wrap up, and put in the fridge. Add the butter and bake right before eating.

→ What sides go best with these sliders?

They taste awesome alongside a crisp salad, slaw, or roasted veggies. Or serve them with crunchy wedges or sweet potato fries for a heartier option.