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Marinated Portobello California Burger

  • Author: Tessa
  • Total Time: 25 mins
  • Yield: 4 burgers 1x


The true embodiment of a California burger, broiled portobello mushrooms are first tenderized in a wine marinade, then stacked with a slew of fresh, vegan toppings and condiments.



Portobello burgers

  • 4 large portobello mushrooms, stemmed and cleaned
  • 1/2 C dry rosé or white wine
  • 2 T balsamic vinegar
  • 2 T tamari or soy sauce
  • 1 T canola or other oil
  • 4 small garlic cloves, minced
  • 1/2 t truffle salt (or kosher salt)
  • 5 to 10 grinds of black pepper


  • 4 burger buns
  • Mayonnaise (I use Just Mayo – it’s vegan)
  • Mustard (I like the weird yellow stuff, but pick your favorite)
  • 1 avocado, sliced into rounds (see notes)
  • 8 big lettuce leaves
  • Tomato slices from 1 large tomato
  • Thin slices of red onion, rings separated


  1. Place portobellos gills down on a rimmed baking sheet. Mix together all the remaining portobello ingredients to make the marinade. Brush over the tops of the mushrooms, then flip them over and pour remaining marinade over the gills. Let stand one half to one hour, brushing occasionally to make sure marinade is evenly distributed. With 5 or 10 minutes to go, flip caps and brush tops with more marinade, so it really soaks in.
  2. While mushrooms marinate, slice buns and slather each half with a thin coat of mayonnaise, and prepare other burger toppings.
  3. Preheat the broiler and move oven rack about 6 inches from it. Toss mushrooms into a bowl and drain the excess marinade, then wipe down the tray with a paper towel or wash and dry it. Wipe garlic off of mushrooms, and place gills facing up on tray. Broil about 5 minutes, then flip over, emptying juice from the gills, and broil about 5 more minutes, until mushrooms are slightly shrunken and tender all the way through. To keep the mushroom burgers from being overly juicy and messy, set them on a plate lined with a few layers of paper towels. Remove paper towels after a couple minutes.
  4. While mushrooms cook, toast buns in a dry skillet over medium heat on cut side, a few minutes each, until golden. Set aside or keep warm in the bottom of the oven (away from the broiler element).
  5. Build the burgers with your choice of toppings. I liked this order: bottom bun, mustard, avocado, portobello burger, lettuce, tomato, onion, mayo, top bun. Don’t try to be neat and tidy while you eat this one. Cutting it in half helps, but it’s juicy no matter what.


Portobello marinade recipe adapted from Isa Chandra‘s perfect grilled portobellos.

To get round doughnut shapes of avocado: Instead of splitting your avocado lengthwise, cut it crosswise around the fattest part. Remove the pit as you otherwise would, then slice away, peeling each ring individually.

Prep time excludes 30 minutes of inactive marinating.

  • Prep Time: 15 mins
  • Cook Time: 10 mins
  • Category: Entree
  • Cuisine: Burger