Vegan Meatballs

Ingredients

• 16 ounces mixed cremini and shiitake mushrooms, stemmed and sliced
• 1 cup walnuts
• ½ cup coarsely chopped yellow onion
• 2 garlic cloves, grated
• ½ teaspoon sea salt, plus more for sprinkling
• ½ teaspoon freshly ground black pepper, plus more for sprinkling
• ½ teaspoon fennel seeds, toasted
• ½ teaspoon ground cumin
• ½ teaspoon smoked paprika
• ¼ teaspoon ground sage
• 1½ cups cooked black beans, drained and rinsed
• ¼ cup whole rolled oats
• 1 tablespoon extra-virgin olive oil, plus more for drizzling
• 1 tablespoon tomato paste
• 1 tablespoon ground flaxseed
• 1 tablespoon tamari
• 1 tablespoon balsamic vinegar
• ¾ cup panko bread crumbs
• Avocado oil, for the pan
• Marinara sauce, for serving