On a low heat, add the olive oil to a large pan, shortly followed by the shallot. Sauté for a few minutes until translucent.
Add the risotto rice and stir well, allowing this to cook gently until the rice becomes opaque – a couple of minutes.
Deglaze with the wine and allow this to quickly reduce before you can start adding the “stock”.
Add the water one ladle at a time, stirring frequently to help bring out the starch in the rice. Never let the rice completely dry out before adding your next ladle. Risotto is a labour of love, so prepare to dedicate the next 15-20 minutes to nursing and stirring. Continue adding stock by the ladle until the rice is cooked through and with a very slight bite to it. The consistency shouldn’t be gloopy or clumpy – you should be able to use a spoon to part the risotto and it quickly fall back together.
Once the rice is almost there in terms of bite – add the cavolo nero pureé and mix well to combine.
Remove the pan from the heat and let it rest for a few minutes.
For the mantecatura – add the cold butter and grated Parmigiano. Stir to combine, then add the egg yolk and quickly stir to mix through. You can flip the risotto continuously in the pan to help bring it all together – the wave of risotto is what’s called all’onda – resembling a wave.
Season generously with salt – remember we didn’t use stock so seasoning absolutely here is key.
Serve on flat plates – shaking the risotto to spread it across the base – adorned with the fried capers and small pieces of mozzarella.