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Mushroom-Polenta Diamonds

To roast peppers, char them over a gas burner or under the broiler, turning them as they blacken. Place in a bowl; cover with plastic wrap. Let sit 15 minutes. Remove skins, seeds, and ribs.

  • Yield: Makes about 5 dozen
Mushroom-Polenta Diamonds

Source: Martha Stewart Living, December 2003


  • 6 ounces shiitake mushrooms, stems removed, and caps wiped clean
  • 1 tablespoon unsalted butter, plus more for baking sheet
  • 1 small onion, minced
  • 2 tablespoons port or dry white wine
  • 6 tablespoons heavy cream
  • 1 teaspoon coarse salt, plus more for seasoning
  • Freshly ground pepper
  • 1 cup instant polenta
  • 1/2 cup freshly grated Parmesan cheese (2 ounces)
  • 2 roasted red bell peppers, cut into thin slivers, for garnish (optional)
  • Mascarpone cheese, for garnish (optional)


  1. In a food processor, pulse mushrooms until finely chopped. Melt butter in a medium skillet over medium heat. Add onion; cook, stirring occasionally, until softened, about 4 minutes. Add mushrooms; cook until softened, about 3 minutes. Add port, and stir until evaporated. Stir in cream; simmer until mixture is thick, about 3 minutes. Season with salt and pepper. Remove from heat; let cool.

  2. Butter a 10-by-15-inch rimmed baking sheet; set aside. Boil 1 quart water in a large saucepan; add 1 teaspoon salt. While whisking constantly, gradually add polenta. Reduce heat to a simmer; cook, whisking constantly, until soft and all water is absorbed, about 5 minutes. Stir in Parmesan. Immediately transfer to prepared baking sheet; spread evenly. Let cool completely; cover with plastic wrap, and refrigerate until ready to proceed. Polenta can be made up to 1 day ahead.

  3. Halve the polenta crosswise. Carefully transfer one half, smooth side down, to a clean work surface; spread mushroom mixture on top. Place remaining polenta half, smooth side up, on top; trim edges.

  4. Cut polenta lengthwise into 3/4-inch-wide rows; cut rows at an angle to form 1-inch-long diamonds. Place on parchment-lined baking sheets. Wrap in plastic wrap; freeze until ready to use, up to 6 weeks.

  5. To serve, preheat oven to 425 degrees. Transfer sheets to oven. Bake diamonds, rotating sheets halfway through, 12 to 15 minutes. Garnish each with bell pepper and a dab of mascarpone, if desired. Serve warm.

Reviews (6)

  • aussie_oi1 1 May, 2014

    This is quite harsh, but this was just gross. It was such an odd flavour. And 12 hours later its repeating on me. Shame, as I made them for a very exclusive function. I hope someone likes them. (and they were actually very messy looking, they don't come as out neat as the picture would have you believe). I also doubled the recipe and still did not have 5 dozen.

  • kimzsl 3 Nov, 2012

    I entertain a ton and a great cook,in fact my family thinks I need to open my own restaurant. Unfortunately,this recipe was Big disappointment.After the time spent planning & cooking,this is a HUGE disaster.Not sure who the other commenters are cooking for,but my guest & family, would've trashed this- too bland,too much polenta & taste-very boring.I even added chopped up fresh garlic & red pepper flakes to pump up the flavor,but still flopped.Don't waste your time.Very pretty,but not worth time.

  • CorinneCooks 20 Aug, 2011

    I made these for a NYE party and they were a huge hit. Since then, they're a regular request for family gatherings. Chefjanet is right--making them with one cup cream makes them extra creamy (albeit fattening) but very delicious.

  • chefjanet 20 Nov, 2010

    I made creamy polenta using 1 cup cream and 3 cups water. It is delicious and makes this recipe a little more rich.

  • Mena222 15 Nov, 2010

    You won't find polenta in a Spanish grocery. It's Italian. Find an Italian grocery, although most big supermarkets carry it in their "international" section. It is really very easy to make. You can also find it pre-made wrapped in tube like packages like liver sausage. Not my favorite but not terrible. You could cut it into thin rounds and put your filling in between. Polenta is really delicious and worth the effort to try again.

  • GreenE 17 Aug, 2010

    This was a disaster! First, could not find "Instant Polenta" even in the spanish grocery store. Adding regular polenta to boiling water also was a mess. I consider myself an experimental cook and cook for large parties, but this recipe goes in my "never again" round file.

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