Chook and Avocado Sandwich with Verjuice Mayonnaise Recipe

Name: Chook and Avocado Sandwich with Verjuice Mayonnaise Recipe
Yield: 6
Ingredients: [HEADING]Chook & Avocado[/HEADING]; 4.0L Maggie Beer Free Range Chicken Stock; 6 whole black peppercorns; 2 bay leaves; 285g chicken breast (1 large); 1 1/2 avocados, peeled and sliced lengthways; To serve young rocket leaves; 6 slices bread; [HEADING]Verjuice Mayonnaise[/HEADING]; 180g free range egg yolks (approx. 9); 1/3 cup (80ml) Maggie Beer Verjuice; 1 tspn finely grated lemon zest; 1/2 tspn Dijon mustard; 1 tbspn chopped french tarragon; 1 1/4 tspn sea salt; 3/4 cup (180ml) Maggie Beer Extra Virgin Olive Oil; 3/4 cup (180ml) grapeseed oil