Brush the chicken and zucchini with the lemon juice and olive oil. Season with black pepper and set aside at room temperature for 20 minutes.
Heat the olive oil in a large pan and add the onions and sage and preserved lemon. Cook on a medium heat for 15 - 20 minutes until the onions have browned and thickened.
Chargrill the chicken for 5 minutes each side. Transfer to a baking sheet and bake in the oven for a further 10 minutes.
Chargrill the zucchini for 5 minutes each side.
Serve the chicken over the caramelised onion and top with grilled zucchini.
Note: Sage is a lovely ancient herb with a soft velvety flavour. It is rumoured to have numerous health benefits including alleviating fatigue and and stimulating regrowth of liver tissue.