Start off by cutting the ends off. Removing the skin from the onion and then grate the onion. Put the onion in a tea towel and drain out all the liquid. Then put into the bowl with the rest of the ingredients for the meatballs. Give a good mix with a pinch of pepper. Form into about tennis ball size meatballs and let chill in the fridge for at least 20 minutes.
Add oil to a deep dish and start frying off the meatballs in batches.
To make the sauce start gently frying the garlic and then stir in the chill powder and basil. After a couple minutes add in the tomato’s, vinegar and sugar and bubble away for 15 minutes or until sauce has thickened.
Finally add the meatballs to the sauce. Tear up the mozzarella and add it on top. Cook for another 20 minutes and serve.