Heat vegetable oil in a large saucepan over medium-high heat. Stir in quinoa, onion, bell pepper, and garlic; cook and stir until onion tender and quinoa lightly toasted, 5 to 10 minutes.
Stir in water and tomato sauce; season with chili powder, garlic powder, and cumin. Bring to a boil, then reduce heat to medium-low, cover, and simmer until quinoa tender and liquid absorbed, about 30 minutes, stirring occasionally.
