Preheat the Oven: Set your oven to 180C/350F for standard baking or 160C/320F for fan/convection settings.

Prepare the Vegetables: Pile the sliced mushrooms onto a baking tray, drizzle with olive oil, toss them gently, and spread them evenly. On another tray, spread the drained cannellini beans and sprinkle the grated carrot across them.

Bake the Beans and Mushrooms: Place the tray of beans on the top shelf of your oven and the mushrooms on the shelf below. Bake for 15 minutes until the beans’ surface is dried out and splitting, with the carrots around the edges turning golden brown.

Finish Baking the Mushrooms: Remove the beans tray, move the mushrooms to the top shelf, and continue baking for an additional 10 minutes until they are dried out and wrinkly. Let them cool after removing from the oven.

Prepare the Cashews: In a food processor, pulse the cashews until they resemble small breadcrumbs, taking care not to pulverize them into a powder.

Combine Ingredients: In the food processor, add the beans, cooled mushrooms, and grated carrot. Blitz on high for about 10 seconds until they are chopped but not pureed. Then, include the breadcrumbs, egg, parmesan, garlic, paprika, mayonnaise, salt, and pepper. Blitz again for 15 to 30 seconds until the mix is combined yet still textured.

Incorporate Rice and Green Onions: Add the cooked brown rice and sliced green onions. Blitz for just 2 seconds to combine without turning the rice gluey. Adjust the consistency by adding breadcrumbs if too wet, or blitzing longer if too crumbly.

Form the Patties: Shape the mixture into 4 to 6 patties about 1.5 to 1.8 cm (0.6 – 0.7") thick and 10 cm (4") wide. Place the patties in the refrigerator for at least an hour to firm up.

Cook the Burgers: Heat 2 to 3 tablespoons of olive oil in a skillet over medium to medium-high heat. Add 3 to 4 patties to the skillet and cook until deep golden and crispy, about 4 minutes per side. Transfer to a paper towel-lined plate to drain.

Grill Option: Alternatively, brush the veggie patties with oil and grill over medium-high heat for 4 minutes on each side until a dark crust forms.

Assemble the Burger: Toast your buns and spread the top bun with your favorite relish or sauce. Layer with lettuce, sliced tomato, and any other toppings you desire, placing the Veggie Burger on top and adding more sauce if you like.