Begin by slicing the leeks, finely dicing the onion, cutting the bacon into small pieces and mincing the garlic.
Add the oil and half of the butter to a large heavy-based pan and fry the onions, leeks, bacon and garlic for 5 minutes until the vegetables begin to soften until beginning to soften.
Dice the chicken and toss into the pan. Cook, stirring frequently until sealed on all sides.
Pour the rice and black pepper into the pan and stir to coat in oil. Let cook for a minute, stir and let cook for another minute.
Add the wine to the pan, give everything a good stir and then let the liquid evaporate.
Toss the thyme into the pan.
Now start adding the stock, a ladleful (75ml) at a time, stirring between each addition until it is absorbed. After 20 minutes test the rice to see how well it is cooking. If it is still firm keep adding a bit more stock. If it feels almost ready then move on to the next step.
When the rice is almost cooked add a little more stock along with the peas and artichokes. Test the rice again after 5 minutes. It is ready when it feels al-dente (there's still a little bite to the rice but, essentially, it doesn't feel firm or chewy)
Take the pan off the heat, remove any large stems of thyme, stir in the Parmegiano-Reggiano and the remaining butter, cover the pan with a lid and let the risotto sit for 5 minutes. Season with salt to taste. Stir well before plating up.