Romesco Sauce Recipe - Easy, Versatile & Delicious

Ever tried a sauce that’s smoky, nutty, garlicky, and tangy all at once? That’s romesco sauce for you! Hailing from Catalonia, Spain, this incredible roasted tomato and nut sauce is traditionally served with charred green onions called calçots during lively outdoor parties known as calçotadas. But don't let tradition limit you – this recipe red sauce is a total game-changer for grilling season, elevating everything from veggie platters to simple weeknight dinners.
Forget bland meals! Our easy romesco sauce recipe is your new secret weapon. It’s naturally vegetarian gluten free and can easily be made dairy free too, making it one of the best recipes for leeks (or calçots!) and a fantastic gluten free dairy free meal option. Whether you’re a beginner cook looking for easy to make recipes for dinner or an experienced food lover, get ready to dive into the rich, vibrant flavors of the Pyrenees right in your own kitchen!
Romesco sauce is a classic Catalan sauce, deeply rooted in the fishing communities of Tarragona, Spain. Originally made by fishermen to accompany their catch, it quickly became a staple, especially during the spring calçotada season. Its basic flavor profile is a delightful blend of smoky (from roasted peppers), nutty (almonds and hazelnuts), garlicky, and tangy (vinegar). It's a robust sauce that brings a burst of Mediterranean sunshine to any dish.
While often confused with salbitxada, another Catalan sauce commonly served with calçots, romesco typically features roasted tomatoes and dried ñora peppers, giving it a deeper, richer flavor, whereas salbitxada often relies more on raw tomatoes and garlic. This recipe focuses on that classic, robust romesco flavor you’ll love.
Best for: Calçots/green onions, grilled vegetables, fish, chicken, sandwiches, dips.
Diet: Naturally vegetarian; easy gluten-free dairy-free option.

Ingredients

• Nuts:
• 1/2 cup raw almonds, whole or blanched: These provide the essential nutty base and help thicken the sauce.
• 1/4 cup raw hazelnuts (optional): Hazelnuts add another layer of rich, slightly sweeter nuttiness.
• Peppers:
• 2-3 dried ñora peppers (or other mild dried red peppers), stemmed and seeded, soaked in warm water for 20 minutes: These traditional Spanish peppers impart a deep, smoky, and slightly sweet flavor.
• OR 1/2 cup jarred roasted red peppers, drained: A convenient substitute if you can't find ñora peppers, offering a similar roasted flavor.
• Tomatoes & Garlic:
• 1 pound ripe Roma tomatoes, halved: Roasting these brings out their natural sweetness and deepens their flavor.
• Vinegar & Oil:
• 2 tablespoons sherry vinegar or red wine vinegar: Adds a crucial tangy bright note to balance the richness.
• 1/2 cup extra-virgin olive oil, plus more for roasting: The base fat for emulsifying the sauce and enhancing its flavor.
• Thickener:
• 1 slice stale country bread or baguette (about 1 ounce): Helps to bind the sauce and give it body.
• For gluten-free: Skip the bread and add a few more nuts for thickening.
• Seasoning:
• 1 teaspoon smoked paprika (optional but recommended): Enhances the smoky flavor profile.
• 1/2 teaspoon salt, or to taste: Essential for seasoning.
• 1/4 teaspoon black pepper, or to taste: Adds a subtle kick.
• Pinch of sugar (optional): To balance acidity if your tomatoes are particularly tart.

Directions

1. Toast the nuts and bread: Preheat your oven to 375°F (190°C). Spread the almonds, hazelnuts (if using), and stale bread on a baking sheet. Toast for 5-7 minutes, or until they smell nutty and turn lightly golden, not dark brown. Remove and let cool slightly.
2. Roast the tomatoes and garlic: On the same baking sheet (or a separate one), toss the halved Roma tomatoes and unpeeled garlic cloves with a drizzle of olive oil. Roast for 20-25 minutes, or until the tomatoes are soft and slightly caramelized, and the garlic cloves are tender. You can also use good quality canned tomatoes in a pinch – see Ingredient Notes in the Pro Tips section.
3. Build the base paste: Once cooled, peel the roasted garlic. In a food processor or high-speed blender, combine the toasted nuts, toasted bread (if using), soaked and drained ñora peppers (or jarred roasted red peppers), peeled roasted garlic, smoked paprika, and sherry or red wine vinegar. Pulse until you have a coarse, rustic paste.
4. Add tomatoes and emulsify with oil: Add the roasted tomatoes to the food processor. Blend until mostly smooth, then, with the processor running on low, slowly drizzle in the 1/2 cup extra-virgin olive oil until the sauce is thick but spoonable. You’re looking for a thick dip that just barely holds its shape on a spoon.
5. Taste and adjust: Taste the romesco and adjust seasoning. Add more salt or pepper as needed. If it tastes a bit flat, a tiny splash more vinegar can brighten it up. If your tomatoes were very acidic, a pinch of sugar can balance the flavors. For a spicier kick, you can add a pinch of chili flakes.
6. Rest the sauce: Transfer the romesco sauce to a bowl or jar. For the best flavor, let it sit for at least 20-30 minutes at room temperature for the flavors to meld. It can also be stored in the fridge for up to 5 days.
7. Charred Calçots (or Green Onions) IngredientsCalçots are a special type of sweet green onion, similar to leeks but with a milder flavor. If you can't find them, thick green onions or spring onions make a great substitute.
   1. 1-2 bunches calçots or thick green onions/spring onions (about 10-12 total): The star of the show, ready to be charred.
   2. 1 tablespoon neutral oil (like canola or grapeseed), or extra-virgin olive oil: For tossing the onions before charring.
   3. 1/2 teaspoon salt, or to taste: To season the onions.
   4. Optional: Freshly ground black pepper or lemon wedges for serving: Adds extra flavor and brightness.
8. How to Char Calçots (or Green Onions) Step-by-StepThis method works for both calçots and green onions, offering options for your kitchen setup.
9. Prep the onions: Trim the roots off the calçots or green onions, and remove any tough or dry outer layers. Wash them thoroughly and pat them completely dry with a kitchen towel. Toss lightly with the neutral oil and salt.
10. High-heat charring: Choose your preferred method for charring:
    1. Grill (outdoor): Place the oiled calçots directly over high heat on a grill. Cook, turning occasionally, until they are deeply charred on the outside and soft all the way through, about 8-12 minutes.
    2. Stovetop grill pan: Heat a grill pan over high heat until smoking. Add the calçots and cook, turning as needed, until deeply charred and tender, about 10-15 minutes.
    3. Broiler (top rack): Arrange calçots on a baking sheet and place on the top rack under a preheated broiler. Broil for 5-8 minutes per side, watching carefully, until blackened and soft.
11. You want them deeply charred on the outside and soft all the way through.
12. Steam to soften (optional but traditional): Once charred, immediately wrap the hot calçots in foil, parchment paper, or even newspaper. Let them rest for 5-10 minutes. This steaming process helps the centers become wonderfully silky and makes the charred outer layers easier to peel.
13. Serve the calçots: Traditionally, you grab the green top of a calçot, strip away the blackened outer sheath to reveal the tender white core, dip it generously in the romesco sauce, and tilt it into your mouth. It's a fun, hands-on ritual! You can also just cut them into bite-size pieces if you prefer less drama or are serving them as part of a larger dish.