In a food processor, add the basil and a teaspoon of olive oil, and process to a paste. Season the chicken breast, then lightly smear with the basil paste.
Wrap the breast tightly in cling wrap, twisting and knotting the ends to secure them. Immerse parcel in gently boiling water for 15 to 20 minutes, depending on the size of the breast.
Crush a third of the chickpeas with the back of a fork, then gently combine in a bowl with the remaining chickpeas, tomatoes, coriander and rocket. Season to taste and drizzle lightly with the remaining olive oil.
Remove chicken from the poaching water and leave to cool for 2 to 3 minutes, then remove from its wrapping and shred with a fork.
Combine chicken with salad, toss lightly and serve.