Rinse the quinoa then place in a saucepan and add the water and salt. Bring to a boil. Once boiling, reduce heat to a simmer and cover. Simmer 15-20 minutes or until all water is absorbed. Fluff with a fork, add the olive oil and pepper and let cool in a serving bowl.
Blanch the tomatoes in boiling water and peel them. Remove the seeds and dice the flesh.
When ready to serve, dice the cucumber and add it to the quinoa along with the tomatoes, onion, vinegar and 1/4 cup parsley. Mix and taste for salt. Garnish with remaining parsley and serve!