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Crispy Sweet Potatoes With Tuna-Anchovy Mayonnaise

Crispy Sweet Potatoes With Tuna-Anchovy Mayonnaise 4.000

Jennifer Chase for The Washington Post

Jan 8, 2018

At the River Café in London, chefs Ruth Rogers and Rose Gray, who died in 2010, stirred tuna into their homemade mayo. Meanwhile in Los Angeles, Vinny Dotolo of Jon & Vinny’s sneaks caper brine and lemon zest into his tonnato to brighten the sauce without making it overpowering.

In this preparation, the condiment is left thicker, like an aioli, and accompanies smashed, pan-fried sweet potatoes in a re-envisioned Spanish patatas bravas.

More uses for this classic tuna-anchovy mayonnaise: Serve with sliced tomatoes; hard-cooked eggs; or a Nicoise salad.

To read the accompanying story, see: Tradition be damned. This quick Italian sauce suddenly goes with everything.

Make Ahead: You will have tuna-anchovy mayonnaise left over, which can be refrigerated for up to 3 days.

Where to Buy: This mayonnaise contains raw egg, so if that presents a health risk for you, use pasteurized eggs; brands such as Davidson’s are carried at some large supermarkets.


When you scale a recipe, keep in mind that cooking times and temperatures, pan sizes and seasonings may be affected, so adjust accordingly. Also, amounts listed in the directions will not reflect the changes made to ingredient amounts.

Tested size: 4 servings

  • For the tuna-anchovy mayonnaise
  • 1 large egg yolk, preferably pasteurized (see headnote)
  • Finely grated zest and 2 tablespoons fresh lemon juice from 1/2 lemon
  • 3/4 cup extra-virgin olive oil
  • 1 tablespoon brine-packed capers, finely chopped, with 2 teaspoons brine reserved
  • Kosher salt
  • 6 olive-oil packed anchovies, finely chopped
  • Freshly ground black pepper
  • One 7- to 8-ounce can or jar good-quality tuna packed in olive oil, drained
  • For the potatoes
  • Kosher salt
  • 1 pound sweet fingerling potatoes or very small sweet potatoes
  • 10 tablespoons extra-virgin olive oil
  • 1 large clove garlic, coarsely chopped
  • A few sprigs fresh thyme
  • A few sprigs fresh rosemary
  • 4 ounces fresh chorizo, in pinches (casings removed; about 3/4 cup)
  • Freshly ground black pepper
  • Crushed red pepper flakes (optional)


For the tuna-anchovy mayonnaise: Combine the egg yolk and 2 teaspoons of the lemon juice in the bowl of a stand mixer fitted with a balloon-whisk attachment; beat on medium-high speed. Gradually drizzle in some of the oil, letting it slide down the side of the bowl. Beat until thickened, then stop. Add 2 more teaspoons of the juice, plus the reserved caper brine; this should loosen up the mixture.

Continue to beat (medium-high), drizzling in the remaining oil, to form a thick mayonnaise. Season lightly with salt. The yield is about 1 1/4 cups.

Combine the anchovies, the remaining lemon juice and a pinch of the black pepper in a small bowl, stirring to coat, then stir that mixture, and the capers, into the mayonnaise.

Use a fork to mash the tuna in a separate bowl, breaking it up into small pieces. Stir into the mayonnaise, along with the lemon zest, until well incorporated. Cover tightly and refrigerate until ready to use (and up to 3 days).

For the potatoes: Line a baking sheet with paper towels. Bring a large pot of water to a boil over high heat. Salt it generously. Add the sweet potatoes and cook for about 15 minutes, until tender. Transfer the potatoes to the baking sheet to drain. Use a spatula to crush each one flat.

Heat a large cast-iron skillet, gradually increasing the heat from low to medium-high. Add 3 tablespoons of the oil. Once it is shimmering, add the sweet potatoes and season them with a couple of pinches of the salt. Press the potatoes into the pan and cook for about 10 minutes, undisturbed, until their bases begin to brown.

Flip the sweet potatoes; add 3 more tablespoons of oil to the pan along with the garlic. Season with another pinch or two of the salt. Cook for 5 minutes, watching the garlic and stirring it, as needed, to prevent burning. Flip the sweet potatoes again and add 2 more tablespoons of the oil and a few sprigs each thyme and rosemary. Cook for another 5 minutes, then flip the sweet potatoes one more time. Add the remaining 2 tablespoons of oil and the chorizo. Cook for 5 minutes more to brown and crisp up the chorizo and render its fat.

Transfer to a platter. Season lightly with salt, black pepper and the crushed red pepper flakes, if using. Spoon a few dollops of the mayonnaise over the potatoes.

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Recipe Source

Adapted from “The River Café Classic Italian Cookbook,” by Rose Gray and Ruth Rogers (Michael Joseph, 2009).

Tested by Bonnie S. Benwick.

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Nutritional Facts

Calories per serving (using 1/2 cup of the mayo and 6 tablespoons olive oil for the potatoes): 550

% Daily Values*

Total Fat: 46g 71%

Saturated Fat: 8g 40%

Cholesterol: 45mg 15%

Sodium: 500mg 21%

Total Carbohydrates: 24g 8%

Dietary Fiber: 3g 12%

Sugar: 5g

Protein: 12g

*Percent Daily Value based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

Total Fat: Less than 65g

Saturated Fat: Less than 20g

Cholesterol: Less than 300mg

Sodium: Less than 2,400mg

Total Carbohydrates: 300g

Dietary Fiber: 25g

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