Mix the pork mince, breadcrumbs, egg, half the crushed garlic and a good pinch of salt and pepper in a bowl. Squeeze the mixture through your fingers until it just comes together, then roll into 16 walnut-sized meatballs.
Heat the oil in a large frying pan over a medium-high heat and brown the meatballs in two batches for about 5 minutes per batch, turning until golden all over. Lift them onto a plate.
Turn the heat down to medium, add the chopped onion to the same pan and fry for 5 minutes until soft, scraping up the tasty brown bits from the base.
Add the remaining garlic, the chopped tomatoes, tomato puree, oregano and half a tomato tin of water. Simmer for 5 minutes until slightly thickened.
Return the meatballs and any juices from the plate to the pan, cover and simmer gently for 10 minutes until the meatballs are cooked through and the sauce clings to them. Season to taste.
Serve over rice with the sauce spooned over everything.