• Cook Time 4 hours
  • Total Time 4 hours
  • Yield 4 7-oz burgers 1x
Author Mushroom Council

Try top chef Stephanie Izard’s blended burger: a blend of shiitake mushrooms and ground beef topped with asparagus tapenade and rhubarb mostarda. You’ll quickly learn why she says she likes it better than a regular burger!

Watch Stephanie make her blended burger – then try it at home with the recipe below!

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  • 1 1/2 pounds 80/20 ground beef
  • 1 pound shiitake mushrooms, stems removed
  • 2 teaspoons Kosher salt
  • 2 cups Asparagus Tapenade (recipe below)
  • 1/2 cup Brown Butter Miso Aioli (recipe below)
  • Spread Rhubarb Mostarda (recipe below)
  • 1 cup arugula
  • 1 tablespoon extra virgin olive oil
  • 4 large burger buns

Asparagus Tapenade

  • 2 cups asparagus, woody stems removed, greens sliced into 1/4-inch rounds
  • 1/4 cup Nicoise olives, roughly chopped
  • 2 tablespoons fresh mint, roughly chopped
  • 1/2 tablespoon preserved lemon or lemon zest

Brown Butter Miso Aioli

  • 2 tablespoons white miso
  • 2 tablespoons brown butter
  • 1/2 cup mayonnaise
  • 2 teaspoons lemon juice
  • 1/4 cup sour cream

Rhubarb Mostarda

  • 2 cups rhubarb, sliced
  • 1 cup white wine vinegar
  • 1/2 cup sugar
  • 1 tablespoon mustard seeds
  • 1/2 teaspoon Dijon


  1. Preheat oven to 325 degrees.
  2. Toss shiitake mushrooms in cooking oil and season with salt. Roast shiitakes for 12-15 minutes, until tender. Allow to fully cool before processing in a food processor or finely mince by hand.
  3. In a stand mixer with a paddle attachment or by hand, incorporate meat, ground mushroom and salt to a homogenous mixture. Patty into 4 equal sized burger patties. Rest in the refrigerator for at least 30 minutes.
  4. ASPARAGUS TAPENADE: Heat a sautepan over medium heat. Add a small splash of oil to the pan and saute asparagus until just tender, about 2 minutes. Transfer to a bowl and allow to cool. Once cooled mix withnicoise olives, fresh mint andlemon. Refrigerate until ready to use.
  5. BROWN BUTTER MISO AIOLI: Preheat oven to 350 degrees. Spread misoon a sheet tray and brown in the oven for 4 minutes. Stir and cook for another 3 minutes until medium caramel color. Remove from oven and cool completely.

    Blend toasted miso, brown butter, mayonnaise and lemon juice until smooth. Transfer to a bowl and fold in sour cream.Can be stored in refrigerator for 3 days.

  6. RHUBARB MOSTARDA: Bring vinegar and sugar to a boil. Whisk to dissolve sugar. While hot pour 1 tablespoon over mustard seeds. Set aside remaining vinegar and allow to cool to room temperature. Pour cooled vinegar over rhubarb and allow to sit for 2 hours.

    Strain and rough chop 1 cup pickled rhubarb and mix with pickled mustard seeds and Dijon. Remaining pickled rhubarb can be stored in the refrigerator for up to a month.

  7. BUILD YOUR BURGERS: Sear or grill burgers to desired doneness. Toss arugula in olive oil and a small pinch of salt and set aside. Spread bottom bun with 2 tablespoons brown butter miso aioli and top with a ½ cup Asparagus Tapenade. Top with cooked blended burger patty and dressed arugula. Spread top bun with rhubarb mostarda. Enjoy!

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