Mushroom Burger with Tomato Relish & Vegan Aioli

Ingredients

Burgers

• 6 Tbsp. avocado oil, divided
• 14 oz. black oyster or maitake mushrooms,
• either in 2 or 4 clusters
• 2 Tbsp. cornstarch
• 15 large sprigs fresh thyme
• 2 tsp. salt
• 1 Tbsp. black pepper
• 4 green onions, roots trimmed

Vegan Aioli

• Makes 1 cup
• ¼ cup aquafaba
• (the liquid from canned chickpeas)
• 2 tsp. Dijon mustard
• 2 tsp. lemon juice
• 1 tsp. maple syrup
• 1/2 tsp. salt
• 1/2 tsp. garlic, minced
• 3/4 cup avocado oil

Tomato Relish

• Makes 1 cup
• 1 cup red and yellow cherry tomatoes, divided
• 1 Tbsp. capers
• 2 tsp. sherry (or rice wine) vinegar
• 1/4 tsp. salt
• 1/2 tsp. black pepper

For Serving

• 2 burger buns
• 1 cup baby arugula or baby sorrel leaves

Directions

1. Prepare tomato relish and aioli first. To make the aioli, add all ingredients except avocado oil to the food processor. Purée for 1 to 2 minutes or until mixture is white and foamy. Using the chute, very slowly drizzle the oil into the food processor while keeping it running. It should be a fine stream of oil, taking roughly 2 minutes to pour the full amount. Continue to process for another minute until the aioli has thickened to the consistency of mayonnaise. Taste for seasoning, then remove from the food processor, transfer to an airtight container and set aside.
   
2. To make the tomato relish, heat a heavy skillet to medium heat. Add half of the tomatoes to the pan and toss until they start to char and blister. Remove from the pan and set aside to cool completely. Meanwhile, cut the remaining tomatoes into quarters and place them in a medium-sized bowl. Add the capers, vinegar, salt and pepper. Once the charred tomatoes are cooled, cut them into halves. Add to the relish and gently mix.
   
3. Sprinkle and toss mushrooms in the cornstarch and let sit for 5 minutes. Preheat skillet to medium heat and add 4 tablespoons of oil and thyme.
   
4. Place the mushrooms in the pan and cook for 2 minutes.
   
5. Press down on the mushrooms with the bottom of another skillet. Cook for 5 minutes. Turn the mushrooms over. Mushrooms should be deep golden-brown.
   
6. Add the 2 remaining tablespoons of oil and cook for another 5 minutes, then press down on the mushrooms again with the bottom of the skillet. Remove mushrooms from the pan and season both sides with salt and pepper.
   
7. In the same frying pan, add the green onions and toss with tongs for 5 to 10 minutes or until wilted and starting to char. Remove from heat and set aside.
   
8. Toast the split burger buns. Spread the bottom halves of the buns with the aioli. Divide the mushrooms between the two burgers. Top with green onions, tomato relish and fresh greens. Spread more aioli on the inside of the top bun and place on the burgers. Serve immediately.