Why make homemade tomato paste when it’s always available at the grocery store? I use tomato paste all the time. Sometimes I need up to half a cup, and sometimes just a little bit. When I make my own, I can store it in the sizes I tend to need most, so I have no more partly used cans in the fridge.
The hardest part of the process is squishing the tomatoes, separating the pulp from the skin and seeds. I use the fruit strainer attachment to my KitchenAid stand mixer, but you can use a hand-crank version, as I did for years. If you process a lot of tomatoes – and I do – a motorized strainer is a blessing.
I’ve made tomato paste 2 easy ways: roasting it in the oven, or cooking it in slow-cookers. Let me tell you the pros and cons of each method.
roasting
Pro: easy, amazingly easy, and fuss free. Con: you run the oven for 4-5 hours, and if it’s a very hot day, that can be a problem. Gotcha: it helps to have wide flat pans without tight corners. Pro tip: you don’t have to run your oven in the hottest part of your day! Tip #2: you don’t have to can the tomato paste the same day as you roast it: you can easily refrigerate it to deal with the next day. If you’ll be freezing some, it’s already chilled. If you’ll be canning it, remember to bring the tomato paste back up to hot before packing it into jars.
Link to recipe: oven-roasted tomato paste
slow cooker
Pro: easy and mostly hands-off. Con: you need a lot of space, possibly 2 6-qt slow cookers, so it takes up counter space. It takes a long time, probably 2 days or so. Gotcha: you need wide and flat slow-cookers, not tall narrow ones. Pro tip: you don’t have to can the tomato paste the same day as you roast it: you can easily refrigerate it to deal with the next day. If you’ll be freezing some, it’s already chilled. If you’ll be canning it, remember to bring the tomato paste back up to hot before packing it into jars.