Start by cooking quinoa (the approximate 10 minutes time depends on your quinoa). Drain in a sieve, pour it in a dish and stir together the quinoa and one tablespoon of olive oil. Let it cool down.
When quinoa is cold, prepare the other ingredients. Remove the stems from herbs and finely chop leaves. Very finely mince onion (or shalloand cut tomatoes into very small cubes.
Combine those ingredients with quinoa. Add salt and pepper. Season to your taste with more or less lemon juice and olive oil.
Notes
The main steps: Cook and drain quinoa. When quinoa is cold add chopped fresh herbs and minced tomatoes and onion. Combine and season. Serve chilled.