Peel the red onion, cut it into thin circles and pour ice water for 10 minutes to remove the bitterness. Then drain the water, dry it and cut it into 4 parts.
Wash the chicken breast, dry it and beat it with a hammer to a thickness of 1.5 cm. Unfold the frying pan, put the chicken fillet on one half, cover with the other half of the baking sheet. Press down with the palm of your hand.
Heat a dry frying pan over the fire and put the wrapped chicken fillet on it. Cook on low heat for 7 minutes on each side.
Drain the liquid from the pineapples and cut into small slices.
Wash the cucumber and cut it into thin half rings.
Cut the chicken breast into thin slices.
For dressing, whisk lime juice and olive oil in a small bowl. Add salt and pepper to taste and whisk again.
Put the red onion, cucumber slices and pineapple in a bowl, add the dressing and mix. Put the salad and chicken pieces on a serving dish and sprinkle with herbs.