Steak Crostini with Creamy Horseradish Sauce and Caramelized Onions
I’m Alex, and I believe great food should be simple. This recipe for steak crostini uses tender steak, sweet caramelized onions, and a zesty horseradish cream on crispy toast. It is an easy yet impressive appetizer perfect for your next gathering.
- Prep Time: 20 min
- Cook Time: 40 min
- Total Time: 60 min
- Yield: 12 servings 1x
- Category: Appetizer
- Method: Pan-Frying
- Cuisine: American
- Diet: Vegetarian
Ingredients
Scale
- 1 pound beef tenderloin or flank steak
- 1 tablespoon olive oil, plus more for brushing
- Salt and black pepper to taste
- 1 baguette, sliced into 1/2-inch thick pieces
- 2 tablespoons unsalted butter
- 2 large yellow onions, thinly sliced
- 1/4 cup dry red wine or beef broth
- 1/2 cup sour cream
- 2 tablespoons prepared horseradish
- 1 teaspoon Dijon mustard
- 1 tablespoon fresh chives, chopped, for garnish
Instructions
- Prepare the caramelized onions: Melt butter in a skillet over medium-low heat. Add the sliced onions and cook slowly, stirring occasionally, for 25 to 35 minutes until deeply browned and sweet. Add the red wine or broth, scrape up any browned bits, and cook until the liquid evaporates. Set aside.
- Prepare the horseradish cream: In a small bowl, whisk together the sour cream, prepared horseradish, and Dijon mustard. Season with a pinch of salt and pepper. Cover and chill until ready to use.
- Cook the steak: Season the steak generously with salt and pepper. Heat 1 tablespoon of olive oil in a cast-iron skillet over medium-high heat. Sear the steak for 3 to 5 minutes per side for medium-rare, depending on thickness. Remove the steak from the pan and let it rest on a cutting board for 10 minutes.
- Prepare the crostini: While the steak rests, brush both sides of the baguette slices lightly with olive oil. Toast them in the oven at 375°F (190°C) for 5 to 8 minutes, flipping once, until golden brown and crisp.
- Slice the steak thinly against the grain.
- Assemble the crostini: Spread a layer of the chilled horseradish cream onto each toasted baguette slice. Top with a few slices of steak, followed by a small amount of caramelized onions.
- Garnish with fresh chopped chives before serving immediately.
Notes
- You can use leftover cooked steak for this recipe, which makes assembly even faster.
- For a richer flavor on the toast, lightly rub a cut clove of garlic over the warm crostini before adding the toppings.
- If you prefer a tangier topping, substitute half of the sour cream with plain Greek yogurt in the horseradish cream.
Nutrition
- Serving Size: 2 crostini
- Calories: 210
- Sugar: 3
- Sodium: 280
- Fat: 12
- Saturated Fat: 5
- Unsaturated Fat: 7
- Trans Fat: 0
- Carbohydrates: 15
- Fiber: 1
- Protein: 13
- Cholesterol: 45