Melt the butter in a heavy-based saucepan over a low heat. Add the rice and stir, cooking for 2-3 minutes, or until the rice become translucent around the edges. Add the wine and cook for a further minute, or until it evaporates.
Add a ladleful of warm stock to the pan and stir the rice. When all the liquid has been absorbed add another ladleful of stock and continue doing so until all the stock is used up and the rice is tender.
Stir the beetroot and spring onion into the rice. Season to taste with salt and freshly ground black pepper and set aside to cool.
Roll the rice into 8-10 balls. Flatten each ball and place a piece of mozzarella into the centre, and then fold the rice around the cheese.
Roll the risotto balls in flour, then egg, then breadcrumbs.
Heat enough oil to shallow fry in a deep, heavy-bottomed pan. The oil is ready when a breadcrumb dropped into it will sizzle gently. (CAUTION: Hot oil can be very dangerous. Do not leave unattended.) Carefully place a few risotto balls into the hot oil and fry for a 3-4 minutes, or until the outside is brown and crisp. Cook the risotto balls in batches, removing with a slotted spoon when cooked. Drain on a plate lined with kitchen towels.
Blanch the asparagus in a pan of boiling water, carefully remove from the pan and set aside to cool. Meanwhile heat a griddle pan. Cook the asparagus for one minute on each side and then coat with a little of the olive oil.
Serve the risotto balls with the asparagus and dressed salad leaves.