Black Bean Vegan Burger

Name: Black Bean Vegan Burger
Ingredients: Black Beans, recipe follows; 2 cups cooked brown rice; 1 cup chopped portobello mushroom; 1/2 cup shredded carrots; 1/2 cup panko breadcrumbs; 1/2 cup chopped green onion; 1/2 cup diced sweet onion; 1/2 cup ground flaxseed; 2 tablespoons chipotle in adobo sauce; 2 tablespoons sriracha; 1 teaspoon salt; 1 teaspoon vegan Worcestershire sauce; 1/2 teaspoon smoked paprika; 1/2 teaspoon red pepper flakes; 5 tablespoons olive oil; 6 brioche buns; 6 store-bought vegan cheese slices; Lettuce, sliced red onion, sliced tomatoes; Vegan Chipotle Mayo, recipe follows; 2 pounds black beans; 2 cups vegan mayonnaise; 1/2 cup chipotle in adobo sauce; 2 tablespoons minced garlic; 2 tablespoons horseradish