For 4 Person(s)
Bring a large pot of water to boil. Add the lentils and cook for 20-30 minutes, until the lentils are very tender. Drain and set aside to cool slightly.
In a large skillet, heat the 2 tablespoons olive oil or medium high heat. Add the onions and sauté for 5 minutes, stirring frequently. Add the carrots and sauté for 5 minutes until softened. Add the tomato paste and sauté for 1-2 minutes; remove from heat.
Place the vegetable mixture in a food processor with the cooked lentils, oregano, thyme, basil, and salt. Pulse the mixture for several minutes until partially broken down into a sticky, thick mixture. Transfer to a large bowl. Add the walnuts, breadcrumbs, Parmesan cheese to the food processor and pulse 5-10 times or until the consistency resembles crumbs. Add these crumbs to the large bowl and stir to combine with the lentil mixture. Add the beaten eggs and stir or mix with clean, washed hands until everything is combined. Chill the mixture in the refrigerator for 30 minutes to help it stay firm.
Preheat the oven to 375 degrees. Line a baking sheet with parchment paper. Roll the chilled mixture into golf ball sized balls and place on the baking sheet. Drizzle the top of each meatball with about a teaspoon of olive oil and bake for 20-30 minutes, until the meatballs reach your desired firmness.
Place the baked meatballs into a baking dish with higher sides and pour the sauce over the meatballs. Top with Mozzarella cheese and cover with well-oiled foil to prevent sticking. Turn the heat up to 400 degrees and bake for 10-15 minutes or until the cheese is melted and the sauce is bubbling. Remove from the oven and sprinkle with fresh parsley.