Season the chicken breast in slices with a pinch of salt, pepper, a drizzle of oil and cook in the blast chiller preheated with the function of cooking at low temperature at 75°C for 1 hour and 30 minutes, then cool quickly for about an hour.
Wash the cucumber well and grate keeping the skin, season with a pinch of salt and pepper and let it rest for a few minutes. In the meantime, cut the tomato into cubes, removing the seeds and finely chop the onion. Squeeze the cucumber well and mix with the tomato, onion, yogurt, a drizzle of oil and a little pepper.