Cook ½ cup uncooked quinoa in 1 cup of water according to package instructions.
Heat 1 Tbsp olive oil in a large saute pan over medium heat. Add sliced button mushrooms, diced red onion, diced green bell pepper, and minced garlic. Stir and cook for 10 to 15 minutes, or until mushrooms have released their moisture and excess moisture has all evaporated.
Blend mushroom mixture in a food processor until smooth. Add black beans and cooked quinoa. Pulse just a few times to combine.
Stir in panko breadcrumbs, egg, and spices.
Cover and chill mixture in the fridge for at least 30 minutes (up to 24 hours).
Scoop ½ cup sized portions of the burger dough, then use your hands to form them into patties.
To cook on the stove: Place patties on a greased saute pan over medium-high heat. Cook each side for 5 to 10 minutes, or until golden brown and firm.
To cook on the grill: Set patties on a greased piece of aluminum foil over medium/high heat. Cook each side for about 7 minutes, or until golden brown and firm.
To cook in the oven: Arrange patties on a greased baking sheet and bake at 400°F (204°C) for 15 to 20 minutes, flipping once during cooking.
Serve on a hamburger bun with your favorite burger toppings.
