Portobello Buffalo Burgers with Celery Apple Slaw Recipe

Portobello Buffalo Burgers with Celery Apple Slaw Recipe

  • 1 medium onion, chopped
  • 10 ounces portobello mushrooms, trimmed and quartered
  • 2 tablespoons plus 2 teaspoons olive oil, divided
  • 1 pound ground buffalo
  • 2 celery ribs
  • 1/2 Granny Smith apple, cored (left unpeeled)
  • 1 tablespoons mayonnaise
  • 1 1/2 teaspoons cider vinegar
  • 1 teaspoon olive oil
  • 1 teaspoon whole-grain mustard
  • Rounded 1/4 teaspoon sugar
  • Equipment: an adjustable-blade slicer fitted with 1/8-inch julienne blade
  • Accompaniment: 4 hamburger buns or kaiser rolls, split and toasted
  1. Pulse onion and mushrooms in a food processor until finely chopped. Heat 2 tablespoons oil in a 10-inch heavy skillet over medium heat until it shimmers. Add mushroom mixture, 3/4 teaspoon salt, and rounded 1/4 teaspoon pepper and cook, stirring occasionally, until vegetables begin to brown and liquid has evaporated, 8 to 10 minutes. Transfer to a bowl and cool to warm, stirring occasionally, about 15 minutes.
  2. Cut celery and apple into 2-inch-long thin julienne with slicer.
  3. Whisk together mayonnaise, vinegar, oil, mustard, sugar, rounded 1/8 teaspoon salt, and 1/8 teaspoon pepper in a medium bowl. Add celery and apple, tossing to coat. Let stand 15 minutes to develop flavors.
  4. Mix buffalo into cooled mushroom mixture with your hands until well combined. Form into 4 (4-inch) patties.
  5. Heat remaining 2 teaspoons oil in a 12-inch heavy skillet over medium-high heat until it shimmers. Cook burgers, turning once, about 8 minutes total for medium-rare.
  6. Serve burgers, topped with slaw, on buns.