In a medium saucepan, combine the rinsed quinoa and vegetable broth (or water). Bring to a boil.
Once boiling, reduce heat to low, cover, and simmer for about 15 minutes or until all the liquid is absorbed. Remove from heat and let it sit for 5 minutes, then fluff with a fork.
While the quinoa is cooking, prepare the vegetables. In a large mixing bowl, combine the halved cherry tomatoes, diced cucumber, diced bell pepper, finely chopped red onion, chopped parsley, and mint.
In a small bowl, whisk together the lemon juice, olive oil, salt, and pepper.
Once the quinoa has cooled slightly, add it to the bowl with the vegetables. Pour the lemon dressing over the salad and gently mix until everything is well combined.
If using, sprinkle the crumbled feta cheese on top before serving.
Notes
Serve chilled or at room temperature, garnished with parsley and lemon wedges.