Rinse the quinoa under cold water. In a medium saucepan, combine quinoa and water and bring to a boil. Reduce heat, cover, and simmer for 12 to 15 minutes until quinoa is fluffy and water is absorbed. Remove from heat and let cool.
Meanwhile, chop the vegetables: dice red bell pepper and cucumbers; halve cherry tomatoes; dice avocado just before serving to prevent browning.
In a large bowl, combine cooled quinoa, black beans, corn, tomatoes, bell pepper, cucumber, avocado and cilantro.
Whisk together lime juice, olive oil, cumin, chili powder, salt, and pepper to make the dressing. Drizzle over salad and toss to coat. Chill for 15 minutes if preferred.
Notes
For meal prep, store in airtight containers up to 4 days in the refrigerator. Add avocado just before serving if possible for best texture.