Ingredients

The following ingredients have 5 Servings
  • 2 small (12 to 16 oz) Yukon Gold potatoes or 1 large russet potato (peeled if desired and cut into 1/2-inch (12-mm) cubes)
  • 3 tablespoons olive oil
  • 1 pound mushrooms ((preferably 1 portobello mushroom, 12 cremini mushrooms, and 10 shiitake mushrooms))
  • 1/2 teaspoon dried thyme (or 2 teaspoons fresh thyme)
  • 2 tablespoons balsamic vinegar
  • 1 cup cooked barley
  • 1/2 teaspoon salt
  • 1/4 teaspoon freshly ground black pepper
  • 4 to 6 soft, squishy hamburger buns

Instruction

  • Steam or boil the potatoes until fork-tender, 20 to 30 minutes or so. Drain the potatoes. Transfer to a plate and mash half of them with a fork.
  • Meanwhile, trim the stems from the mushrooms and discard. Scoop out the gills from the portobello and discard. Cut the cap into 1/2-inch chunks. Thinly slice the cremini and shiitake caps.
  • Preheat the oven to 375°F (190°C).
  • Heat 1 tablespoon oil in a large skillet over medium heat. Cook the portobello and thyme for 6 to 8 minutes, until the mushroom begins to soften and throw off its liquid. Add the creminis and shiitakes and cook for 10 minutes, until they've thrown off their moisture and all the liquid has completely evaporated. Add the vinegar and cook, stirring, for 30 seconds or so.
  • Transfer the mushroom mixture to a food processor and pulse until coarsely chopped or, if you prefer, finely chop the mushroom mixture by hand. Dump the chopped mushroom mixture into a bowl and, using your hands, add half the mashed potato along with the barley, salt, and pepper. If the mixture isn't sticking together properly, mash the remaining potato and add it to the mixture, a little at a time, until everything begins to cling together. Shape the mixture into 4 to 6 burgers.☞TESTER TIP: Mixing everything until it sticks together is critical when it comes to the ability of your resulting burger to stick together. In the words of author Lukas Volger, if what results is "too wet, it squeezes out the other side of the bun, and if it's too dry, it crumbles." It's a delicate balance. Trust us.] 
  • In a large ovenproof skillet over medium-high heat, heat the remaining 2 tablespoons oil. Add the burgers, working in batches if necessary so as not to crowd the skillet, and cook until browned on each side, 6 to 10 minutes total. The burgers tend to be somewhat delicate, so flip them only once, preferably using a thin, flexible metal spatula.
  • Move the skillet to the oven and bake for 12 to 15 minutes, until the burgers are firm and cooked through. Place on buns and have at it—carefully, though, as the burgers tend to be on the crumbly side of things. Originally published May 14, 2012.