Delicious and savory roast beef crostini with a creamy horseradish sauce - served two ways! This simple appetizer is perfect for holiday entertaining or your next dinner party.

Crostini is such a versatile appetizer. While a lot of crostini have lighter toppings such as this blackberry goat cheese crostini, this appetizer is very hearty. While people often think of this roast beef crostini as a delicious fall or holiday appetizer, it's really perfect any time of year.

The nice thing about this roast beef appetizer is you can really mix up the toppings. For this recipe, I'm pairing the roast beef with horseradish cream and one version with caramelized onions and the other with pickled onions. They're both delicious! But you can also mix it up and try adding arugula, blue cheese or even capers. Yum!

Ingredients

Roast Beef
Horseradish
Sour Cream
Salt and Pepper
Caramelized or Pickled Onions
Crostini
Garnish such as Chives or Parsley

How to Make

Horseradish CreaM

Horseradish and roast beef are such a classic combination! This appetizer uses a simple horseradish cream sauce, which is super easy to make.

You add the horseradish, cream, sour cream, and salt and pepper to bowl and mix. That's it! You can also buy pre-made horseradish cream to make this easy appetizer, even easier. The horseradish cream sauce can be make up to three days in advance.

Caramelized and Pickled Onions

The nice thing about both caramelized and pickled onions is that they can both be made in advanced. For caramelized onions – thinly slice about 2 onions and cook in a pan over medium heat for 45 minutes to an hour. You can check out the full recipe and tips and tricks here.

For picked onions – slice the onions and add to a bowl or jar with vinegar, aromatics such as peppercorns, and a teaspoon or so optional sugar, if desired. Let sit for at least an hour but preferably at least 24 hours. You can read the full recipe with tips and tricks here.

Assembling the Crostini

You assemble the first crostini by adding caramelized onions, roast beef, horseradish cream and the second by adding roast beef, horseradish cream, and topping with pickled onions.

Tips for making Roast Beef Crostini

You can use deli roast beef or homemade roast beef, both are delicious!
To make this easier, you can use pre-made horseradish cream instead of making it yourself.
If you don't want to bother with caramelized or pickled onions, add sliced red or green onions instead!
All of the components of this recipe can be made ahead of time and assembled the day of.

Making this appetizer ahead of time

This is a great party appetizer because you can make all the parts ahead of time and then assemble the day of.

You can toast the crostini in the morning, make the caramelized onions, pickled onions, and horseradish sauce all can be made up to 2-3 days days ahead of time. You can even purchase pre-made horseradish sauce to make these even easier.

Then when you're ready to serve, just assemble and serve! It's a delicious and simple appetizer that will surely wow at your next party.

Looking for More Easy Appetizers? Check these out!

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