Rinse quinoa in a fine-mesh sieve. Bring vegetable broth and quinoa to boil in a saucepan. Reduce heat to low, cover and simmer until quinoa is tender about 15-20 minutes, Set aside to cool.
In a medium bowl, combine lemon juice, olive oil, maple syrup, salt, cumin, cilantro and spring onion. Combine quinoa, cucumber, tomatoes, sweet corn, and avocado in a bowl. Pour dressing over quinoa salad and toss to coat. Serve immediately.
In a large bowl, toss quinoa, cucumber, tomatoes, sweet corn, and avocado. Pour dressing over quinoa salad and toss to coat. Serve immediately.