eggplant burgers with caramelized onions and horseradish-mustard mayo

You’re all set for summer. (Or any of the other seasons.)
Note: This recipe makes around 6 burgers, depending on how thick you make them.

eggplant burger with caramelized onions

Eggplant Burgers with Caramelized Onions and Horseradish-Mustard Mayo
 
The rich flavor of eggplant with sweet onions and tangy, creamy sauce -- you're all set for summer (or any of the other seasons). This recipe makes around 6 burgers, depending on how thick you make them.
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Ingredients
For the horseradish-mustard mayo:
  • ½ cup vegan mayo (I use Hampton Creek Just Mayo)
  • 2 tablespoons horseradish mustard (I use Annie's Naturals; make your own by combining drained, prepared horseradish and Dijon mustard)
  • Salt
  • Black pepper
For the eggplant burgers:
  • 2½ pounds of eggplant, peeled and cubed
  • Olive oil (to coat eggplant cubes and for frying burgers)
  • 1 cup diced scallions
  • 2 cloves garlic, minced
  • 2 tablespoons finely chopped fresh parsley
  • 1 heaping tablespoon nutritional yeast (Bob's Red Mill and Red Star Yeast are brands most commonly found in markets)
  • ½ teaspoon salt, plus more to taste
  • Black pepper
  • 1¼ cup panko
Instructions
For the horseradish-mustard mayo:
  1. Combine mayo and horseradish mustard, whisking together until smooth. Season with salt and pepper.
  2. Cover and refrigerate for at least 30 minutes so that flavors will meld. (You can make this a day ahead.)
For the eggplant burgers:
  1. Preheat oven to 400 degrees.
  2. In a large bowl, drizzle olive oil over eggplant cubes and toss to fully coat.
  3. Line two baking sheets with parchment paper and spread eggplant cubes on baking sheets in single layer. Roast for 30 minutes, tossing cubes once halfway through to ensure even cooking. When the cubes are very tender, remove from oven and transfer to a large bowl. Mash the eggplant cubes with a potato masher or pulse a few times in a food processor until eggplant is, well, a big pile of mush and no big chunks remain.
  4. Stir scallions, garlic, parsley, nutritional yeast, salt, and black pepper into eggplant mixture. Stir in 1 cup of panko to start. Mixture should be firm enough to hold together when making the burgers. If necessary, add the remaining ¼ cup of panko to stiffen the mixture (I find I almost always need it). Taste mixture and season with additional salt and pepper if necessary.
  5. Cover mixture and refrigerate for at least 30 minutes so it can firm up. (Note: If you're planning to top the burgers with caramelized onions, I suggest getting the onions on the stove at this point so they're ready around the time your burgers are done.)
  6. Divide mixture into about 6 parts, depending on how much you've got and how thick you like your burgers; I generally make mine around an inch thick. Using either a hamburger press (I've got my mother's Tupperware one from the '70s!) a biscuit cutter, or your hands, form the eggplant mixture into burgers. Make sure to pack them tightly if you're using your hands or a biscuit cutter instead of a press! Let burgers rest a few minutes before cooking.
  7. Add 1 to 2 tablespoons of oil to a pan and place over a medium-high heat (do not let the oil smoke). With a spatula, place burgers into pan, but do not crowd them. (These fellas are delicate; leave space so you can get your spatula in there to flip them. I cook only 2 at a time.) Allow burgers to cook until you can see them getting golden on one side. With your spatula, gently turn burgers over and allow to brown on the other side. When the second side looks golden brown, you should be able to flip them more easily. Continue to cook burgers until they're as dark/crispy on the outside as you like.
  8. Remove burgers from pan and place on your favorite egg-/dairy-free buns (toast the buns if you like). Top with caramelized onions (or raw onions if you prefer), lettuce, tomato, and horseradish-mustard mayo.
Notes
This recipe calls for around 2½ pounds of eggplant because eggplant vary so greatly in size. I suggest weighing them at the market to make sure you're starting with the right weight. If you're unable to get a weight and really have no idea what you're working with, I suggest adding seasonings in smaller increments to start and building up (based on your taste) as you go.