What cut of steak is best for Steak Crostini?

Lean, tender cuts like flank steak, sirloin, or tenderloin are ideal. They cook quickly and can be sliced thinly against the grain for optimal tenderness on a crostini.

How can I prevent my Steak Crostini from getting soggy?

Toast the bread until crisp, and assemble the crostini just before serving. You can also create a barrier by spreading the horseradish sauce or a thin layer of cream cheese on the crostini first, before adding the steak and onions.

Can Steak Crostini with Horseradish Sauce & Caramelized Onions be made ahead of time?

Partially. The caramelized onions and horseradish sauce can be made 1-2 days in advance. The steak can be cooked and sliced a few hours prior, but for best results, toast the crostini and assemble immediately before serving to maintain crispness.

What's the best way to caramelize onions for crostini?

Slice onions thinly and cook them slowly over low to medium-low heat with a little oil or butter. This gradual process allows their natural sugars to develop a rich, sweet, and golden-brown flavor, which typically takes 30-45 minutes.

How do I make a simple horseradish sauce for steak crostini?

Combine prepared horseradish with sour cream, mayonnaise, or crème fraîche. Season with a touch of Dijon mustard, lemon juice, salt, and pepper to taste. Adjust horseradish quantity for desired heat.

Is Steak Crostini served warm, cold, or at room temperature?

For optimal enjoyment, steak crostini is best served slightly warm or at room temperature. The steak itself can be served warm, but assembling it on freshly toasted bread allows for the best texture contrast.

Steak Crostini with Horseradish Sauce & Caramelized Onions: The Ultimate Party Appetizer 2025

Name: Steak Crostini with Horseradish Sauce & Caramelized Onions
Prep time: 25 min
Cook time: 45 min
Total time: 1 h 10 min
Cuisine: American
Ingredients: For the caramelized onions:; 2 large yellow onions, thinly sliced; 2 tablespoons butter; 1 tablespoon olive oil; 1 teaspoon brown sugar; 2 tablespoons balsamic vinegar; Salt and pepper to taste; For the horseradish sauce:; 1/2 cup sour cream; 1/4 cup mayonnaise; 2 tablespoons prepared horseradish; 1 teaspoon Dijon mustard; 1 tablespoon fresh chives, chopped; Salt and black pepper to taste; For the steak and assembly:; 1 pound flank steak, ribeye, or sirloin; 1 baguette, sliced into 1/2 inch thick pieces; 2 tablespoons olive oil; 1 garlic clove, peeled; Fresh parsley or chives for garnish; Salt and black pepper for seasoning

Steak Crostini with Horseradish Sauce & Caramelized Onions

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These elegant Steak Crostini feature crispy baguette slices topped with tender steak, sweet caramelized onions, and a zesty horseradish sauce. Perfect for entertaining, these bite sized appetizers can be partially prepared ahead for stress free hosting.

Author: Harmony
Prep Time: 25 minutes
Cook Time: 45 minutes
Total Time: 1 hour 10 minutes
Yield: 20-24 crostini 1x
Category: Appetizer
Method: Stovetop, Oven
Cuisine: American

Ingredients

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For the caramelized onions:
2 large yellow onions, thinly sliced
2 tablespoons butter
1 tablespoon olive oil
1 teaspoon brown sugar
2 tablespoons balsamic vinegar
Salt and pepper to taste
For the horseradish sauce:
1/2 cup sour cream
1/4 cup mayonnaise
2 tablespoons prepared horseradish
1 teaspoon Dijon mustard
1 tablespoon fresh chives, chopped
Salt and black pepper to taste
For the steak and assembly:
1 pound flank steak, ribeye, or sirloin
1 baguette, sliced into 1/2 inch thick pieces
2 tablespoons olive oil
1 garlic clove, peeled
Fresh parsley or chives for garnish
Salt and black pepper for seasoning

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Instructions

Prepare the Caramelized Onions: Heat butter and olive oil in a large skillet over medium low heat. Add sliced onions and cook slowly, stirring occasionally, for about 25 30 minutes until deeply golden and sweet. Add brown sugar and balsamic vinegar during the last 5 minutes of cooking. Season with salt and pepper.
Make the Horseradish Sauce: While onions are cooking, combine sour cream, mayonnaise, horseradish, Dijon mustard, and chopped chives in a small bowl. Season with salt and pepper. Cover and refrigerate until ready to use.
Cook the Steak: Pat steak dry with paper towels and season generously with salt and pepper on both sides. Heat a tablespoon of olive oil in a heavy skillet over medium high heat. Cook steak for 4 6 minutes per side for medium rare, depending on thickness. Transfer to a cutting board and let rest for at least 10 minutes before slicing thinly against the grain.
Toast the Baguette Slices: Brush baguette slices lightly with olive oil and toast in a 375°F oven for 8 10 minutes until golden and crisp. Rub each slice with the peeled garlic clove while still warm for extra flavor.
Assemble the Steak Crostini: Spread a teaspoon of horseradish sauce on each toasted baguette slice. Top with a few slices of steak, a spoonful of caramelized onions, and a sprinkle of fresh herbs. Arrange on a platter and serve immediately.

Notes

Components can be prepared ahead: caramelized onions keep for 5 days, horseradish sauce for 1 week, and cooked steak for 3 4 days. Assemble just before serving to maintain crispy texture. For gluten free option, use gluten free baguette. Leftover prime rib works beautifully in place of fresh steak.

Nutrition

Serving Size: 2 crostini
Calories: 280
Sugar: 5g
Fat: 12g
Carbohydrates: 22g
Fiber: 2g
Protein: 18g

Find it online: https://harmonymeal.com/steak-crostini-horseradish-sauce-caramelized-onions/