Follow these simple steps to create your Vegan Black Bean Meatball Sub:

1. Preheat the Oven: Preheat your oven to 375°F (190°C) and line a baking sheet with parchment paper.
2. Prepare the Flax Egg: In a small bowl, mix the ground flaxseed with water and set aside to thicken for about 5 minutes.
3. Mash the Beans: In a large bowl, mash the black beans with a fork or potato masher until mostly smooth, leaving some chunks for texture.
4. Mix Ingredients: Add the grated carrots, chopped onion, minced garlic, flax egg, soy sauce, cumin, smoked paprika, oregano, salt, and pepper to the mashed beans. Stir until well combined.
5. Add Breadcrumbs: Gradually mix in the breadcrumbs until the mixture holds together. If it’s too wet, add more breadcrumbs as needed.
6. Form Meatballs: Using your hands, shape the mixture into meatballs, about 1-1.5 inches in diameter, and place them on the prepared baking sheet.
7. Bake: Bake the meatballs in the preheated oven for 20-25 minutes, flipping halfway through, until they are firm and slightly crispy on the outside.
8. Heat Marinara Sauce: While the meatballs are baking, heat the marinara sauce in a saucepan over medium heat until warmed through.
9. Prepare the Rolls: Slice the sub rolls in half and toast them lightly if desired.
10. Assemble the Sub: Place 3-4 meatballs in each sub roll and generously spoon marinara sauce over the top.
11. Garnish: Sprinkle with fresh basil or parsley if using, and serve immediately.

These steps will guide you in creating this incredible Vegan Black Bean Meatball Sub effortlessly.