To stuff the chicken breasts
Make an incision down the length of the chicken breasts, season inside and out. Stuff each chicken breast with lemon zest, thyme, mozzarella and 3 asparagus, close and secure with a toothpick. Set aside the lemon juice.
Heat the clarified butter in a non-stick frying pan. Brown the chicken breasts on all sides for approx. 6 mins., transfer to the prepared dish. Pour the stock into the same pan and loosen any bits that have stuck to the bottom. Mix the cornflour with the reserved lemon juice, pour into the pan, bring to the boil and simmer for approx. 2 mins. Pour into the dish containing the chicken and add the capers and thyme.
Approx. 15 mins. in the centre of an oven preheated to 200°C.