Outback Blooming Onion Sauce Recipe: Tangy Horseradish Cream

This creamy, tangy sauce captures the signature flavor of Outback’s famous blooming onion at home. I’ve perfected the balance of horseradish kick and rich mayonnaise to recreate that restaurant-quality taste.

With just a few simple ingredients and 5 minutes of mixing, you’ll have a dip that elevates fried appetizers, sandwiches, or even burgers. The sharpness cuts through richness beautifully.

Ingredients for Outback Blooming Onion Sauce

Nine ingredients. Five minutes. Restaurant-quality dip at home.

The horseradish is non-negotiable here. Look for prepared horseradish in the refrigerated section—it’s not the same as horseradish sauce (which has mayo already). Bubbies is my go-to brand, but any refrigerated version works. Mayonnaise matters too—Hellmann’s or Duke’s give that creamy richness you want. Skip the light stuff; it won’t hold up the same way.

No horseradish? Fresh grated horseradish root at one-third the amount works, but it’s spicier—adjust to taste. Swap ketchup for tomato paste plus a touch of sugar if needed. The Worcestershire is key for depth, but if you can’t find anchovy-free, soy sauce plus a dash of lemon gets you close. Paprika adds color more than flavor, so skip it if you’re fresh out.

This keeps 1 week in the fridge, but honestly it’s gone within 2 days at my house. Doesn’t freeze well—the mayo separates. Stir before using if it’s been sitting a bit.

Step-by-Step Instructions for Tangy Horseradish Cream

This no-cook sauce comes together in minutes with a simple whisk and a few pro techniques.

Step 1: Combine the Creamy Base

In a medium mixing bowl, add the 1 cup Mayonnaise. I always use full-fat for the richest, most luxurious texture—this isn’t the time for low-fat substitutions. The mayonnaise serves as your foundation, providing that signature creamy backdrop for all the bold flavors to come.

At this stage, the mixture will look thick and pale. That’s exactly what you want. The consistency will loosen slightly as you incorporate the remaining ingredients, but it should maintain a dip-able thickness perfect for blooming onions or fries.

Step 2: Add the Bold Flavor Elements

Stir in the 3 tbsp Prepared Horseradish and 2 tbsp Ketchup. Here’s the thing—the horseradish gives that signature Outback kick, while the ketchup balances it with sweetness and a touch of acidity. Use a rubber spatula to really work these into the mayonnaise, scraping the sides of the bowl to ensure even distribution.

Next, add the 1 tsp Yellow Mustard and 1 tsp Worcestershire Sauce. These two ingredients might seem subtle, but they add depth and complexity. The mustard brings a mild tang, while the Worcestershire contributes umami notes that round out the flavor profile beautifully.

Step 3: Season and Balance the Flavors

Now it’s time for the dry ingredients. Sprinkle in the 0.5 tsp Garlic Powder, 0.5 tsp Paprika, 0.25 tsp Salt, and 0.25 tsp Black Pepper. The garlic powder enhances the savory notes, while the paprika adds a hint of smokiness and a beautiful color.

For a little heat, include the 0.125 tsp Cayenne Pepper. This amount adds just a whisper of spice without overpowering the horseradish. If you prefer a milder sauce, you can omit it, but I find it complements the other flavors perfectly.

Step 4: Whisk and Rest for Optimal Flavor

Whisk everything together vigorously for about 30 seconds until completely smooth and uniform in color. You want all the ingredients fully integrated so every bite delivers that perfect balance of tangy, creamy, and spicy. The mixture should have a pale pink hue from the ketchup and paprika.

Let the sauce rest in the refrigerator for at least 1 hour before serving. This allows the flavors to meld and mellow slightly. I know it’s tempting to dig in right away, but the wait is worth it—the horseradish will soften just enough to create that signature Outback taste.

Give it a final stir before serving. The sauce will keep in an airtight container in the refrigerator for up to 1 week, though I doubt it’ll last that long.

Essential Equipment for Great outback blooming onion sauce

Mixing Bowls

A medium stainless steel mixing bowl is ideal for combining all the ingredients. I prefer Cuisinox bowls—they’re durable, non-reactive, and have a great weight. A 2-3 quart capacity gives you enough room to whisk without making a mess. 💪

Whisk Selection

Use a flat wire whisk for the smoothest, most uniform texture. The OXO Good Grips 11-inch is my go-to—it’s comfortable and reaches the bowl edges perfectly. Avoid balloon whisks; they don’t incorporate the thick mayo as effectively.

Measuring Tools

Precision matters with strong flavors like horseradish. I use a set of stainless steel measuring spoons from Prep Solutions. The ⅛ tsp is essential for the cayenne. For the mayo, a 1 cup dry measuring cup works perfectly.

Storage Containers

Transfer your finished sauce to a 16 oz airtight container. I love the Glasslock brand—their snap-on lids are truly leak-proof. For serving, a small ramekin or dipping bowl makes it easy to share. ❄️

Optional Tools

A rubber spatula helps scrape every last bit of sauce from the bowl. The GIR silicone spatula is heat-resistant and flexible. For easy cleanup, keep a damp kitchen towel nearby to wipe the whisk between uses.

Pro Tip

If you’re making a double batch, a hand mixer on low speed can combine everything in 15 seconds. Just don’t overmix—you want it smooth, not aerated. This sauce is too good to waste any on the sides of the bowl.

Frequently Asked Questions