For fresh or frozen tomatoes: blanch fresh tomatoes in boiling water or slip the peels from the thawing frozen tomatoes. Core and quarter the tomatoes or chop them roughly, and bring up to a simmer in a large pot. Simmer for at least 20-30 minutes, then pass through a food mill or metal sieve, or puree with an immersion blender (or in batches with a regular blender or food processor).

For canned tomatoes: If you are using whole tomatoes, you can squeeze or chop the tomatoes to break them up, or puree them with an immersion blender or food processor. I like to use whole canned tomatoes and puree some of them and squeeze or chop the rest (or use canned diced tomatoes) as I like having some small chunks of tomato in my sauce. You can also use tomato passata for all or part of the tomato component.

Wash, peel, and chop the other vegetables (onions, garlic, bell pepper or celery, and optional mushrooms) and set aside in small bowls or on a sheet tray.

Preheat your stockpot or large heavy pans. If you’re using fresh tomatoes, you’ll probably be reducing the tomatoes in your large sauce pot, and will want to brown the meat in separate pans or an electric roaster. Heat the pans over high heat so that the meat will sear and brown instead of just steaming.

If you are using very lean meat like venison or turkey, you’ll want to use a tablespoon or two of olive or vegetable oil, (do not use butter or margerine). Fattier meats like beef and pork usually do not need additional fat to brown.

Crumble the ground meat into the hot pan (with oil or pan spray if you are using it). Work in batches if necessary to not crowd the pan. You want the meat to brown and develop flavor, not steam and boil, so you may need to add it to the pan gradually unless you are using a wide roasting pan or rondeau.

If your beef is very fatty, you may want to drain some of the excess fat, especially if you plan to store your canned sauce for a long period of time. Too much fat in your sauce can interfere with the jar seals, or take on “off” flavors in storage.

Add the diced onions and salt to the browned meat and stir. The salt will help the onions release moisture to deglaze the pan, so that it doesn’t scorch.

Sweat the onions with the meat until the onions are translucent, stirring and scraping the bottom of the pan regularly. If the pan is scorching, you can add a bit of tomato juice or a few spoonfuls of water or stock to deglaze the pan.

Add the diced celery and/or bell peppers and stir again. Saute for several minutes, then add the garlic and mushrooms. Sweat the mushrooms and continue to stir so the bottom of the pan doesn’t scorch.

Add the dried herbs, chili flakes, and pepper, and stir to combine.

Add the prepared or canned tomatoes and the brown or white sugar to the browned meat and vegetables.

Simmer and reduce the spaghetti sauce over medium-low heat for several hours, stirring regularly and adjusting the heat if necessary to keep the pot from scorching. If you are using fresh tomatoes, this may take a long time (less time if you have only paste tomatoes, more if you have a blend of types of tomato).

Adjust seasoning as needed, adding a bit more salt, sugar, or dried herbs if needed.

Place the hot jars in the preheated pressure canner and seal the lid. Heat on medium heat. Vent the canner for 10 minutes once it starts steaming, then add the weight and bring the canner up to pressure over medium low heat.

Process at 10 lbs of pressure (weighted canner) or 11 lbs (dial gauge). Adjust as needed for your altitude over 1000 sf. Process for a full 60 minutes for pints, or 75 minutes for quarts or mixed batches of pints and quarts.

Turn off the heat after the processing time is up. Let the canner rest undisturbed until the pressure returns to zero- do not remove the weight early to vent the steam faster.

As soon as the pressure releases, carefully remove the lid. Wait another couple minutes, then remove the jars with jar tongs or hot pads, and place them on a towel or cooling rack. Cover with a towel if there are cold drafts.

Leave undisturbed overnight or for at least 8-12 hours when the jars are fully cooled.