- Preheat oven to 400°. Prick sweet potato all over with a fork; rub with 1 tbsp oil, and place on a baking sheet. Roast directly on oven rack until soft, about 1 hour. Let cool. Remove and discard skin; mash flesh with a fork. Set aside.
- Pulse mushrooms and garlic in a food processor until finely chopped. Coarsely grate zucchini on the large holes of a box grater; gather up in a kitchen towel and squeeze out excess liquid.
- Heat 1 tbsp oil in a medium skillet over low. Cook shallot and red pepper flakes, stirring often, until shallot is soft. Add mushroom mixture, zucchini and cook, until vegetables begin to release their liquid but have not taken on any color, about 2 minutes. Transfer to a large bowl and cool slightly. Mix in quinoa, mustard, and season with salt and pepper. Let cool.
- In the same food processor that was used for the mushroom mixture, pulse the walnuts until they are semi coarse. Add to the quinoa mixture.
- Add breadcrumbs, lemon juice, chopped parsley, and about 1/2 cup reserved mashed sweet potato to quinoa mixture and mix well. Taste and season with salt and pepper. If the mixture is too loose, add more sweet potato to bind.
- Divide mixture into 4 portions and form into patties, pressing firmly together with your hands. Heat 2 tbsp oil in a medium skillet over medium heat and cook 2 patties until golden brown and crispy, about 2 -3 minutes per side. Repeat with remaining patties.
- Build burgers with patties, toasted buns, mashed avocado, sliced tomatoes or tomato chutney, Smak Dab Mustard and your choice and sprouts or lettuce.
NOTE: Instead of forming this recipe into patties, they can be formed into “meatballs”! Toss them into salads or pop into a pita for your take on a falafel!
