Prepare the Flax Egg : In a small bowl, combine the flaxseed meal and water. Let it sit for a few minutes until it thickens.

Cook the Vegetables : In a large pan, heat a tablespoon of olive oil. Add the onion and garlic, and sauté until translucent. Add the mushrooms and cook until they release their moisture and become tender.

Mix Ingredients: In a large bowl, combine the cooked lentils, sautéed vegetables, flax egg, breadcrumbs, soy sauce, smoked paprika, thyme, salt, and pepper. Mix well until the ingredients are evenly distributed.

Form Meatballs: Using your hands, form the mixture into small meatballs. Place them on a plate and refrigerate for at least 30 minutes.

Cook Meatballs: In the same pan, heat the remaining olive oil. Fry the meatballs until they are browned on all sides. Alternatively, bake them in a preheated oven at 375°F (190°C) for 20-25 minutes, turning halfway through.

Prepare Roux: In a saucepan, melt the vegan butter over medium heat. Add the flour and whisk continuously to form a roux, cooking for about 2 minutes.

Add Broth: Slowly add the vegetable broth while whisking to prevent lumps. Continue to whisk until the mixture thickens.

Season: Add the soy sauce, nutritional yeast (if using), salt, and pepper. Simmer for a few more minutes until the gravy reaches your desired consistency.

Serve the meatballs hot, topped with the gravy. Pair with mashed potatoes, rice, or your favorite side dish.