Mighty Meatless Burgers

Preheat the oven to 350 degrees F (175 degrees C). Spread walnuts onto a baking sheet.

Toast in the preheated oven until nuts start to turn golden brown and become fragrant, 10 to 15 minutes. Remove from the oven and let cool.

While the nuts are cooling, heat 1 tablespoon oil in a large skillet over medium heat. Add onion to the hot oil and saute until light brown, 5 to 7 minutes. Add mushrooms and garlic; saute until mushrooms are barely cooked, about 4 minutes. Transfer mushroom mixture and any accumulated liquid to a large bowl.

Transfer cooled walnuts to a food processor and pulse until finely ground. Add to the mushroom mixture, along with oats, bread crumbs, eggs, ketchup, Worcestershire sauce, balsamic vinegar, liquid smoke, dill, sage, and pepper. Mix until thoroughly combined and sticky but not wet; if it's wet, add more bread crumbs. Refrigerate for 30 minutes, to overnight.

Form mixture into 8 patties that are somewhat sticky but hold together well.

Heat remaining oil in a large frying pan over medium heat. Add patties and cook until browned on both sides, 3 to 5 minutes total. Add broth and bring to a boil. Reduce heat, cover, and simmer until patties are cooked through, about 25 minutes.