Mix the onion and garlic in with the meat. Add all ingredients and use the egg to bind them together. Be sparing, you may not need the full egg depending on size
Using some flour to mould the meatballs into the desired shapes. Cook for 3-4 minutes on the pan and then transfer to the oven for an additional 15-20 minutes to ensure that they are thoroughly cooked.
To Make the Sauce: Fry the onion, mushroom and garlic until nice and soft. Mix in the mixed herbs and the chopped tomatoes. Allow the mixture to bubble away for about 10 minutes. If using the cream add to the sauce now to enrich it.
Adjust the seasoning and add the meatballs to the sauce. Serve on top of some spaghetti.