1 small sweet potato
6 tablespoons olive oil, divided
Kosher salt, freshly ground pepper
1 portobello mushroom cap
1/2 small zucchini
1 small shallot, finely diced
1/4 teaspoon crushed red pepper
1 cup cooked quinoa
3/4 cup dried breadcrumbs
1 1/2 teaspoons fresh lemon juice
4 sandwich rolls, split, toasted
Guacamole, sliced tomatoes, and sprouts (optional)
Preheat oven to 350°
Prick sweet potato all over with a fork, rub with 1 tablespoon oil, then season with salt and pepper.
Roast directly on oven rack until tender, 30-45 minutes. Cool.
Remove and discard skin , mash flesh with a fork. Set aside.
Remove stem from mushroom, discard.
Pulse cap in food processor until finely chopped.
Coarsely grate zucchini on large holes of a box grater.
Place in a kitchen towel, squeeze out excess liquid.
Heat 1 tablespoon oil in a medium skillet over medium-low heat.
Cook shallot and red pepper flakes, stirring often, until shallot is soft, about 2 minutes.
Add mushroom and zucchini, cook, stirring occasionally, until vegetables begin to release their juice, approximately 2 – 4 minutes.
Transfer to a large bowl.
Mix in quinoa. Season with salt and pepper. Let cool.
Add breadcrumbs, lemon juice, and 1/4 cup reserved mashed sweet potato to quinoa mixture. Mix well.
Taste and adjust seasoning.
If mixture is too loose, add more mashed sweet potato to bind.
Divide mixture into 4 portions and form into patties, pressing firmly together with your hands.
Heat 2 tablespoons oil in a medium skillet over medium heat.
Cook 2 patties until golden brown, approximately 2 – 4 minutes per side.
Season with salt and pepper.
Repeat with remaining 2 tablespoons oil and 2 patties.
Place patties on toasted sandwich rolls.
Add guacamole, sliced tomatoes and sprouts (optional)