Place the chicken breasts each in 1 sous-vide bag (vacuum packed or in ziplock back with displacement method).
Cook the chicken in water bath at 65°C for 1.5 hours if frozen or 1 hour if fresh.
Rinse the quinoa well (several times) and drain.
Cook the quinoa in boiling salted water as indicated on the package (about 15 minutes)
Chop the vegetables. Carrots, cucumber and spring onions look good in julienne (thin strips). The celery can be sliced and the tomatoes quartered.
Chop the herbs.
Toss the vegetables with the herbs, a generous squeeze of lemon juice, olive oil and salt.
Drain any remaining water from the quinoa when it's cooked, if there is any
Add the warm quinoa to the vegetables and toss.
Combine the mayonnaise, mustard, lemon juice (1 Tbps), tarragon, salt, peppar into a cup.
Take the chicken out of the bags and with your fingers pull the chicken apart in strips (it should come undone easily)
Toss the chicken with some sesame seeds and a squeeze of lemon juice.
Add salt and pepper to taste.
Serve the quinoa salad, the chicken and the dressing together.