Season the chicken with salt, pepper and curry. Heat some oil in a saucepan over medium heat, add diced chicken breast and cook.
For dressing, combine smashed avocado, chopped parsley, olive oil, lemon juice, salt and pepper.
In a large bowl, combine cucumber, cherry tomatoes cut in half, red cabbage, cooked chicken, onion and the avocado dressing.
Spoon several tablespoons of the mixture into the center of each lettuce leaf.