Dice the onion and bell pepper. Chop the tomatoes.
Heat the oil in a pot over a medium heat. Add the diced onion and and cook for 5 minutes or until soft and translucent, but not browned.
Add the uncooked quinoa, diced bell pepper, corn, and chopped tomatoes to the pan, then stir in the salt, pepper and spices. Cook for 1 minute, stirring.
Stir in the vegetable broth, bring to the boil then reduce the heat to low, cover the pan with the lid, and simmer for 15 minutes or until cooked and soft. If the liquid boils away then add a little more.
Serve warm or cold topped with slices of avocado, fresh cilantro or parsley, and lime wedges.