Serves 6

This supremely tasty veggie burger gets an awesome hit of ‘meaty’ umami flavor from red miso, chipotle peppers, charred onion and more. Black barley is an heirloom grain that offers rich, nutty notes and a great toothsome texture, though the more common pearl barley can also be used. The adobo sauce from canned chipotle chilies makes a deliciously smoky mayo with a nice mellow spice. Chop up and add some of the chilies, too, if you want to dial up the heat.

Burgers

1/2 cup walnut halves

1/2 cup dried brown lentils (such as French or Pardina), picked over, rinsed

2 bay leaves

5 unpeeled garlic cloves, divided

Salt

1 cup coarsely chopped sweet onion, such as Vidalia

1 tablespoon olive oil

1/2 pound shiitake mushrooms, stems removed and saved for another use, caps coarsely chopped

Freshly ground black pepper

1/2 cup toasted wheat germ (see Notes)

3 tablespoons coarsely chopped flat-leaf parsley

3 tablespoons finely chopped chives

2 tablespoons red or dark brown miso

1 large egg, lightly beaten (optional; see Notes)

1/2 cup cooked black barley or pearl barley (see Notes)

Chipotle-Lime Mayo

1 clove roasted garlic (from burger preparation)

1/2 cup mayonnaise

1 1/4 teaspoons adobo sauce from canned chipotle in adobo

1 teaspoon fresh lime juice

1/4 teaspoon ground cumin

To Assemble

6 lightly toasted hamburger buns

Sliced avocado

Sliced heirloom tomatoes

Green leaf lettuce

For Burgers:

Heat oven to 375ºF with rack in middle. Spread nuts on a rimmed baking sheet and toast in oven until lightly golden and fragrant, 7 to 9 minutes. Remove from oven, transfer to a plate and let cool, then coarsely chop.

Meanwhile, in a medium saucepan, combine lentils, bay leaves, 1 garlic clove and generous pinch salt. Add water to cover by 2 inches. Bring to a boil; reduce heat and simmer uncovered until lentils are tender, but still hold their shape, 18 to 22 minutes, then drain. Remove and discard bay leaves and garlic. Measure and set aside 1 cup lentils (save any remaining lentils for another use).

While lentils are cooking, heat a medium cast-iron skillet over medium. Add remaining 4 garlic cloves; cook, turning occasionally, until skins are blackened on all sides and garlic is very soft, about 15 minutes. Transfer to a plate and let cool. Add onion to the hot skillet; cook over medium heat, stirring occasionally, until charred and just tender, 5 to 7 minutes. Transfer to a plate and let cool. (Dry roasting garlic and onions in this manner results in a tasty charred flavor, and helps eliminate unwanted added moisture.)

Using same skillet, add oil and heat over medium-high until hot but not smoking; add mushrooms and pinch each salt and pepper. Cook, stirring occasionally, until mushrooms are just tender, 3 to 5 minutes. Remove from heat; set aside.

Remove and discard skins from garlic; set aside 1 clove for the mayo. In a food processor, combine remaining 3 garlic cloves, 1 cup lentils, chopped toasted walnuts, wheat germ, parsley, chives, miso, 1/2 teaspoon salt, 1/4 teaspoon pepper, egg, if using, and half of the barley. Pulse until mixture is well combined. Add reserved onion and mushrooms, and remaining barley; pulse 3 to 4 times just to incorporate.

Form scant 1/2 cups of mixture into 6 (3 1/2-inch-diameter) patties. Freeze 20 minutes, or chill in refrigerator at least 1 hour or up to 4 hours. Meanwhile, prepare Chipotle-Lime Mayo.

For Chipotle-Lime Mayo:

In a small bowl, mash together remaining roasted garlic clove with generous pinch salt to form a paste. Add mayonnaise, adobo sauce, lime juice and cumin; whisk to combine. Refrigerate, covered, until ready to use.

Heat a lightly oiled stovetop grill pan or an outdoor grill with a lightly oiled perforated grill sheet on top over medium heat. Grill patties, carefully turning once halfway through, until golden brown and warmed through, 8 to 10 minutes total.

Serve burgers on toasted buns with chipotle-lime mayonnaise and lettuce, avocado and tomatoes.

Notes:

Look for black barley at health food markets or order online.

To cook black or pearl barley: Place barley and generous pinch salt in a medium saucepan; add water to cover by 3 inches. Bring to a boil; reduce heat and simmer uncovered, adding water as needed to keep barley covered by 1 inch, until barley is very tender (the bran will be broken and the creamy center will have popped out), 50 minutes to 1 hour for pearl barley and 1 hour to 1 hour and 20 minutes for black barley. Drain and let cool. Barley more than triples in yield from dry to cooked. I like to cook at least 1/2 cup at a time and use the extra to sprinkle into salads or eat as a side dish.

Wheat germ is sold both toasted and raw. To toast raw wheat germ, spread on a rimmed baking sheet and toast in a 350ºF oven, stirring once or twice halfway through, until lightly golden, 5 to 10 minutes. Transfer to a plate and let cool completely.

The egg helps bind these veggies burgers, making them more stable once cooked. If you opt to omit it, you can add an additional 2 to 4 tablespoons wheat germ, which will also help create a firmer texture.

If you prefer to cook burgers in a skillet: Heat 1 tablespoon olive oil in a 12-inch heavy cast iron or nonstick skillet over medium heat until hot but not smoking. Add patties and cook, carefully turning once halfway through, until golden brown, about 8 minutes total.