No need for peeling or coring—or canning, for that matter. These simple, delicious recipes for homemade ketchup, salsa and marinara sauce will stock your kitchen with peak-season tomatoes for the months to come.

By Ian Knauer Aug. 19, 2021 3:58 pm ET

EACH MONDAY, from late July through September, I preserve tomatoes. In the thick of the season, I go through about 400 pounds a week. I boil them down into ketchup, and marinara sauce, and salsa, and tomato purée, and Bloody Mary mix. I put all these in jars, which I seal with a pressure canner to then sell at farmers’ markets throughout the year. I’ve been preserving tomatoes every Monday, this time of year, since I met the farmer who is now my wife.

Back when we were first dating, I must have noticed a crate of slightly overripe tomatoes at her farm, slated for the compost pile. It would have been a Monday, since that’s the day she and her crew sort through the tomatoes that won’t make it to the next weekend’s market. I must have asked if I could have them to preserve. I’m sure I said something witty like, “The best tomato you’ll ever eat will be rotten tomorrow.” She must have rolled her eyes and said, “Have at it.”

That first year, I plunged the tomatoes, all 50 pounds of them, into boiling water, then slipped off their skins and removed their stem ends before dicing them and boiling them with onion and garlic into marinara sauce. How quaint. The next year, my payload was up to about 200 pounds a week, and it’s been increasing ever since. Out of necessity, I’ve learned a few shortcuts

My biggest lesson came the summer I was 1,200 pounds behind in my processing and needed to contract outside help. The Bauman family runs a small-scale processing plant on the edge of Amish country in Pennsylvania, near where I live. They are famous for their apple butter, but a large part of their business model is processing tomatoes for local farms. You can drop off your vegetables and, a few days later, pick up sealed jars of ketchup, or salsa, or any number of preserved products. Jars cost a few dollars each; farmers then sell them at local markets. That’s why most small-farm ketchup in eastern Pennsylvania tastes the same: It’s all Bauman’s recipe.

I’m pretty particular about recipes; most of my business model is writing them. It took some convincing to get Bauman’s to follow my recipe for salsa that year. In the end, and due in no small part to the size of the order, they conceded.

When I dropped off the produce, I asked for a quick tour, which I was immediately told no one had time for. If you want a tour of Bauman’s, there is a page devoted to that on their website. (It’s just a series of slightly out-of-focus photos and a few sentences explaining the apple butter process. It’s a pretty bad tour, which is understandable. No one at Bauman’s has time for a fancy website build-out, either.) They did let me look into the processing plant, where I saw a huge grinder chewing up whole tomatoes.

I took note and started saving myself a lot of time. Forget the peeling and the stem ends. Now I simply blend whole tomatoes, boil them down to the thickness the recipe calls for and season. My Vitamix blender can handle small, whole tomatoes; any that are larger than a tennis ball I cut in half or quarter before blending. Some recipes require more blending (ketchup or marinara), others are fine a little chunky (salsa).

These days I can keep up with the harvest, about 400 pounds of tomatoes a week. While I jar my sauces, any reasonable person who hasn’t committed to such an absurd volume could easily freeze theirs until they’re ready to use them. My favorite method is to fill sealable quart-size bags, zip them closed removing as much air as possible, and freeze them flat on a sheet tray. Once frozen, the flat bags stack easily in the freezer. Sauces I‘ll use sooner go into the fridge, and any leftover takeout container with a tight-fitting lid will do. The recipes featured here will last several weeks that way. Preserving doesn’t get much easier.

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