A ribeye crostini with caramelized onion is a perfect crowdpleasing appetizer. You can make it to have as a savory bite for lunch or dinner or for appetizers for a gathering. A steak crostini basically tastes like a little steak sandwich!
This steak crostini recipe starts with caramelizing the onions because this is the step that takes the longest. You want your onions to simmer for quite a while, so that you get the best and sweetest flavors in the caramelized onions.
Caramelized onions for beef crostinis
First, cut one yellow or sweet onion into slices, either rings or slivers. Then heat a pan with a little bit of olive oil, and add the onions. Sprinkle on a little sugar, salt and pepper. Let this mixture simmer on low for about 40 to 45 minutes.

French baguette for crostini slices
The next step for any steak crostini recipe is to make little pieces of toast from a baguette. French bread is typically the best. Slice the French bread baguette into diagonal pieces about one quarter to one half inch thick to get small even pieces.
Lay the pieces on a baking pan, and then brush lightly with olive oil.

Ribeye for steak crostinis
For a ribeye crostini, of course you’re going to need… Good ribeye! Start by heating a cast-iron skillet with a little bit of olive oil, about half a tablespoon.
Once the pan is pretty hot (medium high), then add your ribeye steaks. This recipe calls for two steaks. If your pan is large enough, you can cook them at the same time, but if not, you’ll have to do one after the other. You don’t have to wipe out the pan in between steaks.


Sear the steak on both sides, or about three minutes on each side, and then turn the heat down to cook it through. Cook your steak to about to 145°, and then put it aside to rest. Place a little tent of aluminum foil over it as it rests for about five minutes.
Finally, slice your ribeye into thin slices that will go nicely on top of a piece of crostini. Consider cutting the long strips of ribeye into two or three bites to make the steak crostinis easier to eat.

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Making the ribeye crostinis
Finally, once your onions have caramelized, it’s time to assemble your crostinis.
Start by placing your French bread toasts on a platter to serve. Then top each crostini with slices of steak. Brush each piece with a small dollop of horseradish sauce.


Then top the steak horseradish crostini with a small pile of caramelized onions, using the tongs.

How to serve a ribeye crostini
You can simply serve your ribeye crostini as steak crostini appetizers on a platter. Serve them warm or cool.
You can make either the steak or the French baguette toast beforehand, if you’d like. Then you can serve it with 1) warm steak and cool toast or 2) cool toast and warm fresh ribeye. Either way, this is one of the easiest and tastiest beef crostini recipes!
Also try: Turkey Lettuce Cups
Ribeye Crostini With Caramelized Onion
Equipment
- Skillet
- Baking Pan
- cast iron skillet or second skillet
- Tongs
Ingredients
- 1 sweet or yellow onion
- 2 tablespoons olive oil
- ½ teaspoon sugar
- ½ teaspoon salt
- ½ teaspoon pepper
- 2 ribeye steaks
- 1 baguette French bread
- 3 tablespoons horseradish
Instructions
- First, start your caramelized onions because they will take the longest to cook. Slice a whole onion into rings or slivers. Heat the skillet on low heat with about 1 tablespoon olive oil. Add the onions. Sprinkle on some sugar, salt and pepper. Allow the onions to simmer on very low heat for about 40 – 45 minutes, stirring occasionally. The onions are ready when they have become translucent and golden. You may need to add some more oil during the process if some of the onions start to burn.
- Next, prepare crostinis by preheating your oven to 400°. Slice the French baguette on a diagonal into pieces about 1/2 inch thick. Lay the piece on the bread slices on a baking pan and brush some olive oil on each slice. Cook about 6-8 minutes just to crisp them slightly. Set the toasted baguette pieces aside.
- Heat cast iron skillet to medium high heat with a drizzel of olive oil, about 1/2 tablespoon. Once the pan is hot add the ribeye. Cook 2 – 3 minutes on each side, then reduce the heat to medium low and finish cooking, about another 5 to 6 minutes until the meat reaches about 140° according to a meat thermometer.
- Once the steaks are cooked, take them off the skillet and tent them with a piece of aluminum foil for about 5 minutes. Slice the ribeye into thin pieces.
- Arrange the toasted baguette pieces on a platter. Top with slices of ribeye, then a small smear of horseradish.
- Once the onions have caramelized, use the tongs to add a small help to each crostini. Serve warm or cool.