1 can (540 milliliters) black beans, drained and rinsed
1 cup (180 grams) cooked brown rice
3/4 cup (70 grams) panko breadcrumbs
1 teaspoon (5 grams) ground cumin
1/2 teaspoon (3 grams) smoked paprika
1 tablespoon (15 grams) Dijon mustard
2 tablespoons (30 milliliters) canola oil
12 slider buns
Heat one teaspoon (five milliliters) olive oil over medium heat in a large non-stick skillet.
Add onions and garlic and season with salt and pepper. Cook until softened, about three minutes.
Add remaining olive oil and mushrooms. Cook until mushrooms start to brown, about five minutes.
Transfer mixture to the bowl of a food processor and pulse until finely chopped. Scrape mixture into a large bowl.
Pulse walnuts in food processor until very finely chopped. Add to mushroom mixture.
Add beans and rice to food processor and pulse until the mixture resembles a coarse puree. Add to mushroom mixture with breadcrumbs, cumin, paprika, one teaspoon (five grams) of salt, and 1/2 teaspoon (three grams) of pepper. Stir to combine.
Add Dijon and egg; stir to combine. Form mixture into 12 equal patties, a generous 1-1/2 centimeters thick and place on a plate or rimmed baking sheet.
Heat one tablespoon (15 milliliters) canola oil in same pan from step 1 over medium-high heat. Working in batches of six, fry patties until golden and crispy, about three to four minutes per side. Serve on slider buns topped with your favourite burger toppings and condiments.