Tomato sauce is one of those things you can make a million different ways depending on what you're having it with. Since this was going on a pizza I made it pretty basic and thin. This is one of those recipes I'll probably adjust a lot and do a few different versions of based on what I'm making them to go on.
One 28-ounce can of whole, peeled tomatoes
About 14 ounces of water
1/2 of an onion, chopped pretty finely
3 large garlic cloves, minced
3 bay leaves
2 celery stalks, chopped in half length-wise and cut into 1-2 inch chunks
salt to taste
1/2 teaspoon of fresh-ground pepper
1 teaspoon of sugar
a few tablespoons of olive oil
Chop up the onion, pour the olive oil into a large pot and put over medium heat until it thins out a bit, and put in the onion in to cook for a few minutes on low-medium heat while you prep the garlic, tomatoes and celery. I like to put a little bit of salt in to bring out the flavor of certain ingredients at different steps in the process, so once the onions go in I put in a dash of salt and stir the whole thing around. Open the can of tomatoes, and break them apart in the can a bit with a good set of kitchen scissors. Once the onions start softening slightly, put the garlic in and let that cook for about 30 seconds to a minute, until it becomes aromatic. Put in the tomatoes, celery, bay leaves, a little more salt, pepper and sugar in, fill the tomato can about halfway with water and put that in the pot, and bring the whole thing up to a slight boil. Bring it back down to a simmer and let it cook uncovered for about an hour, checking on it and stirring every 10-15 minutes. When it looks like the sauce has reduced as much as you want it to, take the celery and bay leaves out, and dump the rest into a blender (or use an immersion blender in the pot, if you have one) and pulse for about 15 seconds to smooth the whole thing out. Taste test to see if you want more salt, pepper or sugar.
Since I'm using this sauce for pizza that I'll be making shortly, I poured the sauce back into the pot to sit until I need it. If you want to store it for longer than a few hours, let it cool a bit and can it. It'll last about a week in the fridge, longer in the freezer. This is a small batch so one good-size meal and it'll probably be all gone.