Pour the stock into a medium sized saucepan and heat on low whilst you are preparing the risotto base.
Peel and dice the onion and celery into small 1 cm pieces.
Place a large casserole pot or saucepan on the stove and heat for a couple of minutes on a medium heat. Add the olive oil and butter and wait for the butter to melt then add the onion and celery. Cook for 10 minutes, stirring occasionally, until softened.
Add the crushed garlic, stir for about 30 seconds then add the zest of the lemon, the salt and pepper and the rice. Stir the rice well to fry it and coat it with the oil and aromatics for 1-2 minutes.
Pour in the vermouth (or white wine), keep stirring it into the rice and allow it to cook off for 1-2 minutes.
Add a ladleful of the hot stock directly from the saucepan and stir into the rice allowing it to absorb. Once the rice has absorbed all the stock then add another ladleful. Keep stirring all the while so it doesn’t catch on the bottom of the pan. Carry on allowing the rice to absorb the stock and adding more as you need to whilst stirring for about 15 minutes at which point most of the stock will have been used up.
Add the turkey pieces, along with a ladleful of stock, stirring in until they are evenly distributed in the risotto. Keep adding more stock as you need to (maybe another 5 minutes) until the rice is looking and feeling plump without much chalkiness. Make sure not to break the turkey up too much as you are stirring.
Taste to check if the rice is cooked. It should be soft but with a slight bite to the centre (not a crunch).
As soon as you are happy with the texture of the rice (you might not need all the stock) and the liquid has been absorbed then turn off the heat.
Stir the parmesan and egg yolk into the risotto along with a good squeeze of lemon juice. Taste for seasoning, adding more salt and pepper if needed.
Place the lid onto the risotto and allow to rest for 2-3 minutes whilst you get the bowls ready, this helps the risotto settle and finish absorbing all the flavours and stock.
Serve immediately with a sprinkling of fresh parsley and cracked black pepper.