Cook the lentils: in a pot, combine the brown lentils with the water, and bring to a boil. Cover and simmer for 20-25 minutes until the lentils are tender, and prep the rest of the sauce. Alternatively, you can cook the lentils in the rice cooker (**recipe below in Notes) while you prep the rest of the sauce.
In a large pot or large saucepan, heat the olive oil over low heat. Add the onions and garlic, and sauté for 6-7 minutes until the vegetables have begun to soften. Toss in the carrots, mushrooms, tomato paste, diced tomatoes with the juice, Italian seasonings, chili flakes and stir well to combine.
Add the vegetable stock and black tellicherry pepper, stir well, and bring to a boil. Cover and reduce the sauce to a simmer, and cook over low heat for about 20 minutes until carrots are cooked through.
Taste, and adjust seasoning as desired. Toss sauce with your favorite pasta, sprinkle with fresh parsley, and mangia!