Roast Beef Crostini Appetizer with Horseradish Sauce

If you love beef, you’ll LOVE this recipe. This roast beef crostini appetizer with horseradish sauce will quickly become your new go-to appetizer for parties. And, it’s a great way to use up your leftover roast! Anytime I can recreate leftovers into something new is a win in my book. My husband is my official taste tester for all recipes that go on this site. He gave them an enthusiastic 11/10, so I know this one is a keeper. If you love beef, you’ll love this recipe!

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roast beef crostini appetizer with horseradish sauce

Roast Beef Crostini Appetizer with Horseradish Sauce


  • 1 drizzle extra virgin olive oil
  • 1/2 baguette
  • horseradish sauce to taste
  • 8 ounces roast beef
  • 1/3 block shredded gouda cheese
  • crispy fried onions to taste


  • Preheat oven to 350 degrees.
  • Slice baguette into even slices.
  • Drizzle with olive oil.
  • Bake at 350 for 5 minutes.
  • While your baguette is in the oven, shred 1/3 block of gouda cheese.
  • Remove bread from the oven and flip each piece.
  • Add the following toppings to each piece: horseradish sauce, leftover cooked roast beef, shredded gouda and crispy fried onions.
  • Return to the oven and bake at 350 degrees for 7-10 minutes or until golden brown and cheese is melted.
  • Allow to cool, plate and enjoy!


All of the amounts listed here are estimates. The amount of each ingredient you need will depend on how big your baguette is and your taste preferences. For example, some will prefer more or less horseradish sauce to beef ratio. I always encourage you to make it your own according to your own taste. 


One thing to note is that horseradish sauce is different than plain horseradish. There are lots of brands of horseradish sauce that you can buy. Pick the one you like best. You really can’t go wrong!


If you don’t have any leftover roast beef, you can substitute any beef you have on hand. Steak would be fabulous with this. I think you could even use ground beef. Talk about a great way to take something basic and turn it into something a little bougie. That’s what being chic(ish) is all about!


If you can’t find gouda or don’t care for it, you can also use absolutely substitute it for your favorite cheese. Havarti or mozzarella would both be great substitutions.


French’s crispy fried onions are my preferred choice for this recipe. No, they’re not just for green bean casserole! 🙂 They’re like the icing on cake or the cherry on top. They’re just one extra ingredient that makes this recipe to die for! Of course, you can certainly make your own or substitute caramelized onion. If you don’t care for onions, you can also skip them completely.

roast beef crostini appetizer


Need some new kitchen tools? Here are a couple I love that might come in handy when making this recipe.

Favorite Baking Sheets

Olive Oil Dispenser Bottle

If you make this roast beef crostini appetizer with horseradish sauce recipe, I hope you love it!

If you need another appetizer recipe, you may also enjoy these cucumber daisy puff pastries! YUM!

Happy Cooking!

-The Chic(ish) Chick

Want to see more ideas like this? Check out my Instagram, TikTok, or Pinterest pages!


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