Perfect Veggie Burgers

INGREDIENTS

• 2 tablespoons chopped fresh parsley
• 1 cup canned pinto or black beans, drained and rinsed
• Kosher salt
• 6 soft buns, split
• 1 small stalk celery, chopped
• 1/3 cup walnuts, chopped
• 1 small onion, chopped
• Onion rings, for topping
• 2 cloves garlic, chopped
• 5 tablespoons barbecue sauce
• 1/3 cup breadcrumbs
• 1 medium carrot, finely grated
• 2 large egg whites
• 2 teaspoons soy sauce
• 3 tablespoons extra-virgin olive oil
• 1/3 cup quick-cooking barley