How far in advance can I make steak crostini for a party?

You can prepare the individual components (steak, horseradish sauce, and caramelized onions) a day ahead. Keep them stored separately in airtight containers in the fridge. Assemble the crostini no more than 30 minutes before serving to ensure the bread stays crisp.

Can I serve steak crostini warm or at room temperature?

Yes! They're best when the steak is slightly warm and the sauce is chilled, offering a pleasing temperature contrast. If serving at room temperature, just make sure nothing sits out for more than two hours.

What’s the best cut of steak for steak crostini?

Tenderloin or sirloin works best for Steak Crostini with Horseradish Sauce and Caramelized Onions . They're tender, cook quickly, and slice thinly without falling apart, which is ideal for bite-sized portions.

Can I use store-bought horseradish sauce?

You can, but homemade is always better. Store-bought versions tend to be either too mild or overly processed. Making your own lets you control the balance of creaminess and heat, ensuring it complements the steak and onions perfectly.

Steak Crostini with Horseradish Sauce: 5-Star Delicious Party Bite

Ingredients

Units Scale

1 lb beef tenderloin or sirloin steak
1 baguette, sliced
2 yellow onions, thinly sliced
2 tbsp olive oil
1/2 tsp sea salt
1/2 tsp cracked black pepper
1/2 cup sour cream
2 tbsp prepared horseradish
1 tsp Dijon mustard
1 tsp lemon juice
Fresh chives or parsley for garnish

Cook Mode Prevent your screen from going dark

Instructions

Preheat oven to 375°F. Slice baguette, brush with olive oil, and toast until golden.
Season steak with salt and pepper. Sear in hot skillet until medium rare. Rest 10 minutes, then slice thinly.
In a skillet, cook onions with olive oil and a pinch of salt on low heat for 30–45 minutes until caramelized.
Mix horseradish, sour cream, mustard, lemon juice, and salt to make sauce. Chill until ready.
Assemble crostini: spread horseradish sauce, add steak slice, top with caramelized onions, and garnish.

Notes

Make components ahead, but assemble last-minute.
Try different herbs like thyme or tarragon for garnish.
Serve warm for best flavor contrast.

Author: Paula
Prep Time: 20 minutes
Cook Time: 40 minutes
Category: Appetizers
Method: Baking, Searing
Cuisine: American
Diet: Low Lactose

Nutrition

Serving Size: 1 crostini
Calories: 120
Sugar: 2g
Sodium: 180mg
Fat: 7g
Saturated Fat: 2.5g
Unsaturated Fat: 4g
Trans Fat: 0g
Carbohydrates: 8g
Fiber: 1g
Protein: 6g
Cholesterol: 22mg