Hot Roast Beef Sandwich with Caramelized Onions

Best Roast Beef Sandwich Ever

It’s no secret that I love roast beef recipes. I like to make roast beef year-round, not just on the holidays, and a big part of the reason why is because I love the leftovers!

There is so much you can do with leftover roast beef, but my favorite way to use it is by making this incredible hot roast beef sandwich recipe.

I can remember my family’s reaction the first time I made these sandwiches. Talk about WOW. 🤯 They RAVED about them for days on end! I had to go buy more roast beef!

There are plenty of roast beef sandwich ideas out there, but let me tell you that this is the best I have ever tried. The combination of flavors from the remoulade sauce to the cream cheese and sweet caramelized onions is unmatched.

Try making this easy sandwich recipe just once and I promise you will be hooked for life. And if you make them for your family, watch out! They will ask you for them all of the time.

🥩 What to Put in a Roast Beef Sandwich

Because I make roast beef recipes all of the time at home, I get asked constantly what to put in a roast beef sandwich. This is always the recipe I give my friends, and I’m excited to share it with you!

All you need to make this sandwich are sandwich buns (your choice, but I love ciabatta bread sandwiches), roast beef leftovers, remoulade sauce, cream cheese, caramelized onions and, optionally, tomato (not everyone in my family likes the tomato, but I think it’s delicious!).

If you’re thinking, “what do you mean remoulade sauce?” Trust me, you need to try it. Remoulade sauce was originally made for beef recipes, not seafood, and it is incredible with roast beef.

What cut of meat is roast beef?

Roast beef comes in all different kinds of cuts! We have quite a few different roast beef recipes to choose from on the site, from chuck roast recipes and eye round roast to beef tenderloin and prime rib.

Any of these recipes will work perfectly for making a hot roast beef sandwich. You can also use deli roast beef to make these sandwiches – that would be so tasty, too!

Chuck Roast Recipes

Tenderloin Recipes

Prime Rib Recipes

What kind of cheese do you put on a roast beef sandwich?

We use strictly cream cheese to make these roast beef sandwiches and it pairs perfectly with the sweet caramelized onions, savory beef, and tangy remoulade sauce.

Other popular choices are Provolone, American, or Swiss, but we highly recommend trying it with the cream cheese. It is so yummy!

🔥 How to Reheat Roast Beef

1. Add 1 Tbsp. butter to a skillet. Sprinkle in 1 tsp. or so of garlic powder or minced garlic.
2. Add leftover roast beef and ½ cup of leftover au jus or beef broth. Bring to a slow simmer.
3. Once simmering, turn off the heat and allow it to heat through. You only want to warm the roast beef, not cook it further.

This will give you the juiciest roast beef ever! Plus, that additional garlic flavoring will really kick up the taste of your hot roast beef sandwich. Enjoy!

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