Place chicken breasts, carrot, celery, leek, parsley and salt in a saucepan. Cover with water and bring to a boil.
Cook until just, approximately 15 minutes. Remove chicken from pan and cool. Strain stock and reserve. Shred chicken breasts coarsely.
Soak bread slices in 1 cup chicken stock and strain. If necessary, add more stock. Mixture must be creamy.
Heat oil in a saucepan and sauté onion. Add garlic and ají and cook until tender. Add soaked bread and cook for 10 minutes.
Add chicken, nuts and parmesan cheese. Stir in milk. If mixture is too thick, add more chicken stock and stir well. Correct seasoning. Spoon over halved potatoes and garnish with olives and egg wedges. Serve with white rice.