To make the dressing, whisk together all the ingredients, seasoning generously with salt and pepper.

Slice the apple into matchsticks and toss through the lemon juice to prevent browning. Add to a large bowl with the chicken, grapes and celery. Add enough dressing to lightly coat the salad ingredients and combine gently.

When ready to serve, gently toss through the walnuts and salad greens until everything is evenly coated with dressing, reserving some of the walnut pieces to scatter on top.

Serve immediately with a long, cool glass of Wolf Blass Gold Label Adelaide Hills Chardonnay.