Peel the sweet potatoes and roughly chop.
Boil in a saucepan of water for about 15 minutes until sweet potatoes are soft.
Meanwhile spray a lined tray with one kcal spray and add the chicken breasts.
Season well with salt & pepper and spray again.
Cook in a medium grill for about 8 minutes on each side until cooked throughout.
Meanwhile mix the cornflour and skimmed milk in a cup.
Add to a saucepan on a medium heat.
Add the grated garlic, stock, wholegrain mustard and extra light cream cheese.
Bring to a simmer stirring until the cream cheese is melted and the sauce starts to thicken.
Season the sauce with salt & pepper.
Mash the sweet potatoes and season with salt & pepper.
Serve the chicken breasts with the sauce poured over, sweet potato mash and steamed asparagus tips.