Step 1

To make soup base, place all soup ingredients in a 5.5L slow cooker. Pour in enough water to just cover. Set to Low. Cook, covered, for 3 hours.

Step 2

Meanwhile, heat oil in a saucepan over medium-low heat. Cook leek, onion, carrot, celery and garlic for 10-12 minutes or until softened.

Step 3

Transfer leek mixture to slow cooker. Cook, covered, for 2 1 ⁄2 hours. Add sweet potato and parsnip. Cover. Cook for a further 30 minutes or until chicken is very tender and falling off the bone.

Step 4

Transfer chicken to a bowl. Use tongs to remove and discard halved onion, carrot and celery, bay leaves and parsley sprigs. Shred chicken, discarding skin and bones. Return to the bowl. Cover to keep warm.

Step 5

Add the zucchini and chopped parsley to the slow cooker. Cook, covered, for 30-40 minutes or until vegetables are tender.

Step 6

Stir in chicken, lemon rind and juice. Season. Cover. Cook for 15 minutes. Remove from heat. Stir in spinach. Serve with bread, if using.