Preheat oven to 180C. Bring stock to the simmer in a saucepan over medium heat. Add chicken, simmer over low heat for
5 minutes, then set aside to cool in stock (20-25 minutes). Just before serving, coarsely shred chicken. Reserve stock for another use.
Meanwhile, scatter walnuts over an oven tray and roast, shaking occasionally, until golden (3-5 minutes). Set aside to cool, then coarsely chop.
Meanwhile, for basil mayonnaise, blanch basil in boiling salted water until bright green (30 seconds), drain, refresh, drain again and squeeze out excess water. Process basil, yolks, vinegar and mustard in a food processor until well combined, then, with motor running, add oil in a thin steady stream. Season to taste and adjust consistency with lemon juice and a little warm water until a thick drizzling consistency.
Blanch baby green beans in boiling salted water until bright green (1-2 minutes), refresh, drain and combine with remaining ingredients, chicken and walnuts in a large bowl, drizzle over dressing, season to taste and serve with crusty bread.
This recipe is from the March 2011 issue of Australian Gourmet Traveller.