Finely dice the yellow onion and red bell pepper into uniform pieces.
Place a large pot over medium heat and sauté the onion and pepper with two tablespoons of the vegetable broth until they are tender and translucent.
Add the chili powder, ground cumin, garlic powder, sea salt, and black pepper to the pot, stirring for one minute to toast the spices.
Rinse the quinoa and red lentils thoroughly in a fine-mesh sieve, then add them to the pot.
Pour in the tomato puree, the remaining vegetable broth, and the black beans.
Bring the liquid to a gentle boil, then reduce the heat to low and cover the pot with a tight-fitting lid.
Simmer for 20 minutes, or until the quinoa and lentils have absorbed the liquid and reached a thick, stew-like consistency.
Remove the pot from the heat and stir in the nutritional yeast until fully incorporated and creamy.
Ladle the hot chili into a bowl and serve immediately.