To make the pasta dough; knead 600 g flour and 400 g of egg yolks together until you have a smooth, elastic dough. Wrap in cling film and rest in the fridge for 1 hour
For the mint butter; combine 10g lemon juice, 170 g of softened butter and 30g of chopped mint leaves in a bowl and set aside
Peel and quarter 700 g of potatoes and boil in salted water until soft (around 20 minutes). Mash the potatoes and mix with the mint butter and pecorino. Taste and season with salt and pepper
Roll out the pasta using a pasta machine and cut into 5cm discs using a round fluted cutter. Place a spoonful of filling onto each pasta disc and fold over, carefully removing any air pockets as you go and sealing with a little egg wash
Make the fonduta by bringing the 200 g of double cream to the boil and adding the 200 g of grated pecorino. Stir until completely melted, then use a stick blender to achieve a perfectly smooth texture
Bring a large pan of salted water to the boil and cook the ravioli for a few minutes until cooked through. Drain well
Spread the fonduta on the plate and place the ravioli on top of the sauce. Garnish with thin slices of guanciale and a dusting of grated bottarga