Preheat the oven to 180-200˚C.
In a bowl, combine the ricotta, parmesan cheese, egg yolk, chorizo, lemon zest with some salt and pepper. Stir until smooth. Keep aside until needed ,covered with cling film.
Prepare the roasting tray by laying some sliced onions and some garlic on the base.
Next, in between two sheets of parchment paper, line the bacon pieces side by side. Cover with the second layer of paper and using a rolling pin roll to thin and stretch the bacon pieces.
In the centre of each butterflied chicken breast, spoon enough ricotta mixture. It should easily Fold to close tightly.
Place the chicken breasts on the bacon and wrap each chicken breast in the thinned bacon.
Place on the prepared roasting tray over the onions.
Add some herbs if desired and transfer in the oven.
Roast for 25-35 minutes depending on the size of the chicken breast or until cooked through. Check for the chicken to be cooked through before removing from the oven!
Once the chicken is cooked, remove from the oven and serve immediately with your favourite sides.