1. Rinse quinoa under cold water.
2. In a saucepan, bring water to a boil. Add quinoa, reduce heat to low, cover, and simmer for 15 minutes.
3. Remove from heat and let sit, covered, for 5 minutes. Fluff with a fork.
4. In a large mixing bowl, combine quinoa, black beans, corn, red bell pepper, avocado, and cilantro.
5. In a small bowl, whisk together lime juice, olive oil, cumin, salt, and black pepper.
6. Pour dressing over salad and toss to combine.