Rinse and drain quinoa. This step is very important. Quinoa has a natural bitter coating of saponins. You will notice the suds quinoa creates when rinsing.
Place water and quinoa in a saucepan and bring to a boil. Reduce to a simmer, cover and cook until all the water is absorbed, about 10-15 minutes. Add salt.
Put chopped mint, cilantro, cucumber, tomatoes, and jalapeño in a bowl.
Add lemon juice, olive oil, salt, and quinoa. Mix well. Let flavors combine for at least an hour before serving.