1. Rinse the quinoa under cold water using a fine-mesh sieve.
2. In a medium saucepan, bring the water or vegetable broth to a boil. Add the quinoa, reduce the heat to low, cover, and simmer for about 15 minutes or until all the liquid is absorbed. Remove from heat and let it sit, covered, for 5 minutes. Fluff with a fork and let it cool.
3. In a large mixing bowl, combine the cooked quinoa, cooked shrimp, diced avocado, diced bell pepper, chopped cilantro, and diced red onion.
4. In a small bowl, whisk together the lime juice, olive oil, salt, and pepper. Pour the dressing over the quinoa salad and toss gently to combine.
5. Taste and adjust seasoning if needed.
6. Serve immediately, or chill in the refrigerator for a couple of hours before serving to allow the flavors to meld.
7. Optionally, you can add diced cherry tomatoes, cucumber, or crumbled feta cheese for extra flavor and texture.