Make the “meat” – pulse walnuts, mushrooms, and carrots in a food processor until broken down into a chunky paste-like texture. Set aside.
Heat the olive oil over medium heat. Add the diced onion and minced garlic. Sauté for 5-10 minutes until very soft.
Add green chiles, tomato paste, chili powder, and cumin. Stir well to combine, letting the spices bloom for a minute.
Add your “meat” mixture to the pan. Once it mixes in and starts cooking, it should start to resemble chili meat. Let the “meat” cook for 10 minutes or so to soften the vegetables. Season with salt.
Add tomatoes, beans if desired, and water to get the consistency right. Let it simmer for about 45 minutes to soften the vegetables, thicken it up, and let the flavors come together.
Serve with your favorite chili toppings, and enjoy your delicious Vegetarian Chili!