Use 1/4 of an onion and don't take out the core. Smash the celery with the back of your knife. They can be left in big pieces since they are removed after the sauce is simmered.
Put the olive oil and lightly smashed garlic in a pan. Tilt the pan so that the garlic is immersed in oil, and heat over medium-low heat until there are tiny bubbles in the oil.
Add the aromatic vegetables to the pan, and pan fry them until they are browned. Make sure they brown well to draw out their umami and fragrance. Just turn them over occasionally, rather than stirring them.
Turn the heat off to lower the temperature of the oil a little. Add the canned whole tomatoes while crushing the tomatoes with your hands. This way the oil won't splatter.
Add the salt and bring to a boil over medium heat. Turn the heat down to low so that the sauce is just bubbling occasionally. If you use a pan with a wide bottom the sauce will reduce faster. Stir occasionally.
Simmer for 15 to 20 minutes. Take the aromatic vegetables and garlic out, and add honey if needed to neutralize the sourness of the tomatoes. It will make the tomatoes milder.
Shred the basil leaves with your hands and add them to the sauce. Simmer the sauce until it has reduced to about 4/5 its original volume. It's done in about 20 minutes after it comes to a boil.
Put the sauce in storage containers while it's still hot. Cover and store in the refrigerator. For 4 cans of tomatoes, you can use the same amount of garlic and other aromatic vegetables. You can keep the sauce for 2 to 3 weeks in the refrigerator.
The sauce uses just a little salt, so when using it in recipes taste it and add more as needed. The photo shows an eggplant and zucchini pasta.
Story Behind this Recipe
10 years ago, I heard Chef Ochiai (a celebrity chef in Japan) saying that if you roast whole vegetables, you can really bring out their umami and fragrance to make a rich sauce! And that you could store the sauce in the refrigerator! I've been making my own version at home and keeping it on hand since then.
When sautéing the aromatic vegetables, brown them properly in order to make a rich tasting tomato sauce. Then, just simmer! Since the aromatic vegetables are removed, I could keep the sauce in containers sterilized with boiling water for more than a month in the refrigerator. You can use this sauce on pasta, on sautéed chicken, in egg dishes and all sorts of recipes.