Juicy, tender steak, sweet and tangy caramelized onions, roasted peppers, peppery arugula, gorgonzola and a horseradish aioli make a restaurant quality steak sandwich right at home.


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What really makes this sandwich special is the balance between sweet, salty, savory and sour. You get sweet and sour from the onions caramelized in balsamic vinegar and brown sugar. Saltiness from gorgonzola andmore sweetness from roasted peppers. Savory/umami flavors from the steak, peppery arugula and a sour note from the horseradish aioli. 

This sandwich may seem fancy but you don't need a special occasion to make this beauty. Theses sliders are perfect game day watching or an elegant dinner party. They are even great as full size sandwiches for a hardy lunch or dinner.

What You Need For This Recipe

  • Steak - Strip, Sirloin, Flank, Flat Iron
  • Onions
  • Butter
  • Brown sugar
  • Balsamic Vinegar 
  • Roasted Peppers
  • Arugula 
  • Gorgonzola or Blue Cheese
  • Provolone or Swiss Cheese
  • Slider Buns 

Choosing the Best Steak

There are quite a few options for choosing the right steak for a sandwich. I've used flat iron and flank for this recipe and both worked really well and are a cost effective option. Because these cuts are much leaner, meaning less fat, they are best cooked to no higher than medium. 

The more fat your steak has, the more tender it will be. Thus cuts like strip, tenderloin, ribeye and sometimes sirloin can handle high temperatures and still be tender. However make sure cuts like ribeye aren't too fatty or remove some of the fat before assembling the sandwich or else you'll have a few unpleasant bites. 

Ironically the more tender cuts of steak are more expensive. However you can still make an awesome juicy steak sandwich without have to spend a lot of money. Below is my list of the best cuts in order by price point:

Flat Iron - $ | Flank -$ | Sirloin -$$ | Strip - $$$ | Ribeye - $$$ | Tenderloin - $$$$ 

How to Cook The Prefect Steak

As mentioned earlier the more fat your steak has marbled throughout the more tender it will be. If you like your steak medium well to well done it's best to choose fattier cut.

But the biggest factor is cooking the prefect steak is the temperature. The best way to do that is by using a meat thermometer like this one. Cook according to your taste:

Rare: 120°F - 125°F (cool, red center, soft texture)
Medium Rare: 130°F - 135°F (warm, red center, soft texture)
Medium: 140°F - 145°F (pink, warm center, slightly firm)
Medium Well: 150°F - 155°F (lightly pink, warm center, mostly firm)
Well Done: 160°F (no pink, warm center, firm texture) 

How To Caramelize Onions

The caramelized onions really set the sandwich over the top. And I highly suggest you don't make this recipe with out them. Although super super easy to make, they do take a while to cook about 45 minutes total, but they're so worth the time. 

How To Make Ahead

The caramelized onions, horseradish aioli and steak can be made ahead and stored in the fridge for up to 3 days in an airtight container. Alternatively, cooked steak can be frozen. Tightly wrap the cooked steak in plastic warp and seal into a freezer bag for up to 3 months. To re-heat preheat oven to 250 degrees and cook for about 20 minutes or until warmed through. 

Tips For Making This Recipe
  • For leaner cuts like flank and flat iron, cook no higher than medium temperature. If you prefer medium well or well done choose a or tender cut like a tenderloin.
  • Use a meat thermometer to get the best juicy, tender steak 
  • Make up to 4 servings with this recipe for full sandwich instead of sliders.