Make the brine by dissolving the sea salt and brown sugar in the boiling water. Add in the cold water and immerse the chicken breasts. Leave for 30 minutes, but not more than an hour. Remove chicken breasts form the brine, rinse thoroughly and dry with a paper towel.
Set the Bradley Smoker to 140°C (280°F) and smoke the Chicken Breasts using Bisquettes of choice, skin side up for 1 hour, or until internal temperature reaches 70°C when probed at their thickest part.
Remove from smoker and allow to cool. Store in the fridge until needed.
Make a dressing by mixing Dijon Mustard, Balsamic Vinegar, Sugar and Sunflower oil. The dressing should be thick and creamy. Set aside.
Place Walnut Halves in a heavy based frying pan over medium heat, cook for a few minutes to roast them then add butter and sugar. Toss to melt and as soon as the sugar browns, remove from heat, salt lightly and scatter onto a paper towel to cool.
Boil a couple of handfuls of small salad potatoes to tender, drain.
Slice the smoked chicken breasts thinly.
To assemble the salad, divide the potatoes between 4 warmed plates, scatter with slices of avocado, apple, salad leaves and walnuts. Top it all with the thinly sliced smoked chicken and a few drops of salad dressing.