Grilled Steak Crostini with Horseradish Sauce Recipe

Oh, let me tell you about this Grilled Steak Crostini with Horseradish Sauce Recipe—it’s one of my absolute go-tos when I want something that feels fancy but isn’t complicated at all. The way the tender, juicy grilled steak pairs with the zing of horseradish sauce on crisp crostini bites is just magical. It’s perfect for casual dinner parties or a weekend treat when you want to impress without stressing in the kitchen.

What I love most is how versatile it is. Whether you’re whipping it up for a last-minute appetizer or a light dinner alongside a fresh salad, this Grilled Steak Crostini with Horseradish Sauce Recipe never disappoints. Plus, with ingredients you can easily find, it’s totally doable even on a busy day—trust me, once you try it, you’ll want to keep it in your recipe rotation too!

Ingredients You’ll Need

All the ingredients in this recipe work together beautifully to balance rich, sharp, and savory flavors. When shopping, pick fresh, quality produce and a good cut of steak to get the best results—trust me, it makes a world of difference.

• Filet Mignon Steaks: I prefer filet for its tenderness, but any good-quality steak works.
• Olive Oil: Use extra virgin for the best flavor; it’s key for grilling and crostini.
• Steak Seasoning: A mix with garlic and pepper enhances the steak’s flavor perfectly.
• Sour Cream: This is the creamy base of your horseradish sauce—feel free to use full-fat for richness.
• Prepared Horseradish: Adds that signature kick; adjust the amount if you like it milder.
• Dijon Mustard: Gives the sauce a lovely tang and depth.
• Champagne Vinegar: Brightens up the horseradish sauce with a subtle acidity.
• Worcestershire Sauce: Adds umami and enhances savory notes.
• Fresh Chives: Chop these up finely for a mild onion flavor and pretty color.
• Baguette: Day-old works best for crostini—it’s easier to slice thin and gets perfectly crisp.
• Butter: Melted butter brushed on the crostini lends richness and helps achieve golden crunchiness.
• Garlic Clove: Optional but highly recommended—rubbing it on warm crostini gives a subtle garlic boost.
• Onion: Slowly caramelized for sweetness to contrast the horseradish bite.
• Sugar: Just a pinch to help with caramelizing those onions beautifully.
• Balsamic Glaze (optional): Drizzle on top for a sweet and tangy finish that’s absolutely divine.

Variations

I love making this Grilled Steak Crostini with Horseradish Sauce Recipe my own by switching things up depending on the occasion or what’s in season—don’t be afraid to play around. It’s all about what you enjoy!

• Variation: Swap the filet mignon for flank or sirloin steak for a more budget-friendly version without sacrificing flavor. I’ve done this plenty of times, and as long as you slice thinly against the grain, it stays tender and delicious.
• Vegetarian option: Substitute the steak with grilled portobello mushrooms and keep the horseradish sauce for that spicy creaminess—perfect for friends who don’t eat meat.
• Spicy twist: Add a sprinkle of crushed red pepper flakes to the horseradish sauce if you’re craving extra heat. I like this touch when serving to friends who enjoy a little kick.
• Seasonal variation: In fall, I sometimes add a smear of fig jam beneath the steak for an unexpectedly sweet layer that balances the horseradish perfectly.

How to Make Grilled Steak Crostini with Horseradish Sauce Recipe

Step 1: Season and Grill the Steak

Start by patting your steaks dry and rubbing them all over with olive oil and the steak seasoning. This locks in moisture and builds a flavorful crust. I like to preheat my grill or grill pan so it’s nice and hot before you add the steaks—this helps you get those beautiful grill marks and seals in the juices. Cook for about 4-5 minutes per side for medium-rare, depending on thickness, and always let your steak rest 5 minutes before slicing thinly against the grain to keep it tender.

Step 2: Make the Horseradish Sauce

While the steak rests, mix together sour cream, prepared horseradish, Dijon mustard, champagne vinegar, Worcestershire sauce, and finely chopped chives in a bowl. Taste and then season with salt and pepper. The sauce should be creamy with a noticeable horseradish zing—if you’re unsure, start with less horseradish and add more as you go because it can pack a punch!

Step 3: Prepare the Crostini

Cut the baguette into thin 1/4-inch slices. Then mix melted butter with olive oil and brush each slice on both sides. I like to grill or toast mine until they’re golden and crisp—about 2 minutes per side on a hot grill or under the broiler. For a little extra flavor, rub the warm crostini with a smashed garlic clove; it adds such a subtle, fragrant punch.

Step 4: Caramelize the Onions

In a skillet, heat olive oil and butter over medium-low heat. Add diced onions with a pinch of salt and the sugar to help with caramelization. Stir often and be patient—it takes about 20-25 minutes for the onions to turn soft, golden, and sweet. Add a sprinkle of fresh chives if you like an extra onion punch, and drizzle with balsamic glaze just before serving for a gorgeous tangy finish.

Step 5: Assemble Your Crostini

Top each crostini slice with a spoonful of horseradish sauce, then layer on the thin slices of steak and a bit of caramelized onion. If you’re feeling fancy, add a few chopped chives or a balsamic drizzle on top. Serve immediately and watch everyone swoon over your impressive, yet surprisingly simple creation.

How to Serve Grilled Steak Crostini with Horseradish Sauce Recipe

Garnishes

I almost always use fresh chopped chives and a light drizzle of balsamic glaze as garnishes—they add pops of color and that slightly sweet acidity that cuts through the richness perfectly. Plus, they make the presentation look restaurant-worthy without any fuss.

Side Dishes

This recipe pairs wonderfully with a crisp green salad tossed in a light vinaigrette or even roasted asparagus for a simple but elegant meal. I’ve also loved serving it alongside creamy mashed potatoes or some garlicky sautéed mushrooms when we want something heartier.

Creative Ways to Present

For gatherings, I like to arrange the crostini on a long wooden board with small bowls of extra horseradish sauce and caramelized onions for guests to customize each bite. Another idea that’s always a hit is stacking the crostini in a pretty tiered stand for a fun, elevated effect that gets people talking.

Make Ahead and Storage

Storing Leftovers

If you have any leftovers (which is rare in my house!), store steak slices, horseradish sauce, and crostini separately in airtight containers and refrigerate. This keeps everything tasting fresh and ensures your crostini stay crispy instead of soggy.

Freezing

While I don’t often freeze this recipe, you can freeze leftover horseradish sauce in a sealed container for up to a month. I wouldn’t freeze crostini as they lose texture, and steak is best fresh or refrigerated to maintain quality.

Reheating

When reheating steak slices, I gently warm them in a skillet over low heat to avoid drying out. For crostini, pop them under a broiler or toaster oven for just a minute to bring back their crunch. Horseradish sauce is best served cold or room temperature, so add that fresh after reheating your other components.

FAQs

Final Thoughts

This Grilled Steak Crostini with Horseradish Sauce Recipe holds a special place in my kitchen because it brings together simple ingredients into something truly memorable. Whenever I make it, friends ask for the recipe—and it never fails to impress, even if I don’t spend hours in the kitchen. Give it a go, and I’m sure it’ll become one of your favorites too!

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