Preheat the oven to 200C / 400F/ 180C fan.
Place the chicken and bacon on greaseproof lined baking trays.
Roast the chicken for 25 minutes and the bacon for 20 minutes, until cooked through and golden. If using streaky bacon, please use 3 slices and keep an eye on the cooking time as it may not take quite as long.
Meanwhile, bring a pan of water to the boil. Add the egg and boil for 12 minutes. Run under cold water and allow to cool before peeling.
In a small bowl, mix the dressing ingredients together.
When the chicken and bacon are cooked, allow to cool slightly and chop into cubes.
In a clean bowl, mix the lettuce, tomatoes, chives, egg, bacon, chicken and dressing.
Cut the avocados in half and carefully remove the pits. Stuff the avocados with the Cobb Salad filling and top with a crumble of Blue cheese.