To prepare the rice balls, start by boiling the rice in 1.2 liters of boiling salted water, in order to ensure that, once cooked, the water has been absorbed. Cook for about 15 minutes, then dissolve the saffron in a little water and add to the rice that is already cooked, then mix with the butter.
Add the grated cheese, stir well, then pour and level the rice on a large tray and cover it with plastic wrap, for it to completely cool.
For the meat sauce start peeling and finely slice the onion.
Fry the chopped onion in a pan with 2 tablespoons of olive oil and butter, then add the ground meat and sauté over high heat, then add the wine and let it evaporate.
Now add the tomato paste, season with salt and pepper and let it simmer covered for 20 minutes. Halfway through cooking, add the peas.
While the peas are cooking, dice the ham and mozzarella.
Once the rice has cooled completely, take a few tablespoons of it and form a ball in your hand, then make a hole in the ball and add the meat sauce and the cheese.
Then close the hole with rice and give it a pointed shape.
Repeat the process until the rice finishes. Now that you have all the rice balls ready, pour the flour, a pinch of salt and a bit of water on each one.
Then dip the rice balls, one by one, into the batter taking care to cover them entirely (26) and roll them in the breadcrumbs.
In a saucepan heat the oil and bring it to a temperature of 170-180 degrees Celsius, then fry one rice ball at a time or a maximum of two.
When they are golden or brown, remove them and drain them, placing them on a tray lined with absorbent paper.