I'm Italian - does that count?
And I am going to assume that you mean a tomato-based sauce -
First of all - if you want a plain tomato sauce -
Heat your pan, add a bit of olive oil, heat your oil - add your tomato products (fresh tomatoes, crushed or whole peeled canned, puree, paste), and water. If I am using paste and puree, I add on paste can of water and a half puree can of water.
Season to taste with salt, pepper, parsley, garlic, Italian seasoning or basil (I don't like the bitterness of marjoram so I no longer use that), a bit of onion powder. Bring to a simmer and simmer for an hour.
No need to simmer any longer - all those products are already cooked.
If you want a veggie-based sauce - with onions/bell pepper/mushrooms -
Heat your pan, add a drizzle of olive oil, saute your veggies, then add your tomato products and continue as above.
Very easy.