Poach the Chicken: Place the chicken breasts in a saucepan large enough to hold them in a single layer. Add the bay leaf, peppercorns, and lemon slice if using. Cover with cold water by about 2-3 cm. Bring the water to a gentle simmer over medium heat, then immediately reduce the heat to low. Cover the pan and let the chicken cook gently for 15-20 minutes, or until cooked through (the internal temperature should be 75°C). Avoid boiling the water, as this can make the chicken tough.

Cool and Shred: Once cooked, remove the chicken from the poaching liquid and place it on a clean board. Let it cool for at least 15 minutes, until it's comfortable to handle. Once cool, you can either dice it into small cubes or shred it using two forks. I personally prefer shredding for this salad.

Prepare the Mix-ins: While the chicken is cooling, prepare your other ingredients. Finely dice the celery and red onion, halve the grapes, and roughly chop the walnuts and fresh dill. Place them all in a large mixing bowl.

Make the Dressing: In a separate small bowl or a jar, whisk together the mayonnaise, Dijon mustard, and fresh lemon juice until smooth and combined.

Combine Everything: Add the cooled, shredded chicken to the large bowl with the celery, onion, grapes, and walnuts.

Dress the Salad: Pour the dressing over the chicken mixture. Add the chopped dill, salt, and pepper.

Mix Gently: Use a large spoon or spatula to gently fold everything together until all the ingredients are evenly coated in the dressing. Be careful not to overmix.

Chill and Serve: For the best flavour, cover the bowl with cling film and chill in the fridge for at least 30 minutes. What works best for me is letting it rest, as this allows all the flavours to meld together beautifully. Garnish with a little extra fresh dill before serving.