The way your question is phrased makes me think you’re of the school that says “spaghetti sauce” must be time-consuming. That’s far from true, as the quickest sauces are some of the most delicious.
I’m making the assumption that you mean a tomato sauce like the ones that line the supermarket shelves in so many different flavors, only homemade. Marinara, spicy marinara, roasted garlic, three cheese, basil, pepper, meat, sausage, Tuscan herb… while they all purport to be different, when I taste them I wonder if they’re not all pretty much the same base with different additions. Some are chunkier, some are spicier, but other than that, to me they’re all pretty similar.
To my mother-in-law, making spaghetti sauce was a big production. She’d begin by getting out her largest stockpot and sautéing ground beef, sometimes a large chunk of braising beef, hunks of pork, and Italian sausages. Once those were done, she’d remove them and sauté chopped onions and garlic in olive oil. Many cans of chopped Italian pear tomatoes, tomato purée, and a couple of cans of tomato paste were added, the whole brought to the very lowest simmer and allowed to cook for about an hour. Then Italian seasonings — basil, oregano, marjoram — were added along with the meats and the simmering continued. Sometimes she added mushrooms, sometimes peppers, sometimes meatballs. Her belief was, “the longer it cooks, the better it is.”
As a young bride, I wanted to make my husband’s favorite sauce, and I tried. It was never as good as Mom’s; and the last time I made it (years ago), I cooked it too long… and it became acrid. Imagine an 8-quart pot full of bad sauce. There is no rescuing or disguising bitter tomatoes – the whole thing had to go out, and I gave up. With an Italian husband, however, there was no giving up Italian food, so I started making other sauces.
On the other end of the spectrum, there are tomato sauces that cook in 15 minutes or so, and they’re wonderful! When I first tried a tomato sauce that called for a little chopped onion sautéed in butter, with chopped fresh tomatoes added and cooked rapidly just until the juices evaporated, it was a revelation. There are even raw tomato sauces which are tossed with hot spaghetti just before serving. These celebrate the tomato first and foremost, and are a different genre altogether. They must be made from ripe, raw tomatoes in season, in small batches, and used quickly. Sauces of this nature are thinner than long-cooked ones, and are best on delicate pastas like angel hair.
The kind of sauces that simmer longer – up to two hours or more – have more body and more ingredients which blend together to create a harmonious whole. Onion, garlic, sometimes celery and carrot as well, are sautéed in olive oil or pork fat before the tomatoes are added. This creates the base which carries the rest of the flavors.
If you’re short of time, there are three ways you can have your own homemade sauce. If you have a day to devote to making a long-simmering sauce, do it with gusto. Make the largest batch of sauce you can and freeze it in pint-size containers. Two cups of this kind of sauce is usually about the right amount for one pound of a sturdy pasta like rigatoni or penne.
If you only have the time to prep and assemble it to the point of simmering, find a recipe that uses a slow cooker. Usually, other than sautéing the vegetables (and ground meat, if you’re using it; sausage can go in uncooked), all you have to do is add all the ingredients to the cooker, set it to low, and be about your business for six to eight hours. A low setting ensures your sauce won’t scorch if you’re away a little longer, but don’t leave it much longer than eight hours.
Lastly, I encourage you to explore the quick-cooking sauces, especially in summer when local tomatoes are so luscious. Consult any reputable Italian cookbook, or simply Google “quick-cooking tomato” and before you can type the word “sauce”, it will come up for you. Have fun choosing!