Place the quinoa and the chicken stock in a pot. Bring to a boil and then reduce heat to a simmer. Let it cook for 15 minutes until all the water has evaporated. Remove from the pot and set aside.
In a food processor or blender, combine the parsley, cilantro, tarragon, mint and olive oil. Pulse until the mixture turns into a pesto-looking consistency.
Combine the herbed mixture with the cooked quinoa and toss to combine. Taste and season with salt and pepper.
Add the cucumbers, cherry tomatoes and sprinkle with feta cheese to finish.