I don't have any formal formula ....I grew up watching my grandmother make it and learned her way.
1) Add some oil to the saucepan and simmer some minced garlic and a small minced onion.
2) Add your tomato ...you can use crushed, pureed, or even a base jar sauce (just don't let my grandmother know I said that). Add one tablespoon of tomato paste and two cans (paste can) of water or low sodium chicken stock.
3) Stir the tomato mixture while heating until it simmers.
4) Add your sausage/meatballs/meat and continue to stir to prevent sticking to the pan. After the meats cook the fats should prevent sticking/burning.
5) Reduce heat and add some salt, pepper, sugar, and red wine (optional)to taste. I only use about a shot of wine but you can double that if you like wine flavor.
6) Add fresh basil, oregano, rosemary if desired.
7) Allow the sauce to slowly simmer for about an hour (or more, the longer it cooks the better) ...you can remove the meats after 30 minutes so it's easier to stir. Stir from time to time to ensure the herbs and spices are well blended.
1) You can do this in a crock pot ....frying the garlic and onion first in a small sauce pan then follow the same steps. Since the crock pot doesn't get as hot you don't have to stir as much during steps 1-4. I just leave the meats in the whole time and stir it around every 20-30 minutes or so.