Toast the Pepper
Place the peppercorns in a dry pan over medium heat. Toast for 2 - 3 minutes until fragrant, then crush coarsely. Set aside.
Make the Risotto
Heat the butter and olive oil in a large pan over medium heat. Add the shallot and cook gently until soft but not coloured.
Add the rice and stir to coat for 1 - 2 minutes.
Pour in the wine and cook until it has mostly evaporated and the alcohol smell is gone.
Gradually add the warm stock, one ladle at a time, stirring continuously until the liquid is absorbed before adding more. The rice should be creamy and slightly loose, it will firm up once cooled.
Remove from the heat and stir in all the Pecorino, Parmesan, and toasted pepper until the risotto is glossy and rich. Taste and adjust seasoning with salt or a tiny squeeze of lemon if desired.
Chill
Spread the risotto on a tray and refrigerate until completely cold and firm, at least 2 hours or overnight for best results.
Shape the Arancini
Portion the chilled risotto into 50g balls.
Flatten each ball in your hand, place a cube of mozzarella in the centre, then seal and roll into a smooth ball.
Coat
Roll each ball in breadcrumbs, pressing gently to adhere. The chilled rice will help the coating stick.
Fry
Heat the oil in a deep pan to 170 - 180°C.
Fry the arancini in batches for 3 - 4 minutes, until deep golden and crisp. Do not overcrowd the pan.
Drain on kitchen paper and season immediately with salt.
Serve
Grate extra Pecorino over the top and finish with a generous crack of black pepper.
