Add quinoa to boiling water, let simmer covered for 12 minutes & fluff with a fork.
In a small bowl, combine the feta, tomatoes, and olives.
To prepare the dressing, combine the lemon juice, olive oil, zaatar spice, garlic, and salt.
Toss quinoa with vegetables and dressing.
The flavors mingle and are enhanced with time, so prepare slightly in advance.