Tomato puree is silky smooth, free of any seeds or skin that tend to make their way into chopped tomatoes or tomato sauce. It freezes beautifully, keeps in the fridge for up to a week, or can be canned, as explained below (note, canning tomatoes is one of the only times you'll see me calling for bottled lemon juice - you want its reliable acid level when canning tomatoes).
The amounts are flexible here: you can make 1 to 6 pints using the same method depending on how many tomatoes you have on hand.
- Fresh, ripe tomatoes (1 1/2 pounds for each pint jar)
- If you're canning:
- 1 Pint jar, lid, and ring for every 1 1/2 pounds of tomatoes
- 1/4 teaspoon citric acid (or 1 tablespoon bottled lemon juice for each pint jar)
- Starting with clean, dry tomatoes, halve smaller ones and roughly chop larger tomatoes. Remember, these are all going to be puréed, so don't worry about even chopping—you're cutting them just so they release liquid and start cooking down a bit faster. Put them all in a pot and bring to a boil. Reduce the heat to maintain a steady and active simmer of gentle small bubbles popping up here and there. Cook, stirring frequently, until the tomatoes start to break down, 10 to 15 minutes.
- To reduce the risk of burns, let the mixture cool first. Then run the tomato mixture through a food mill or whirl quickly in a blender or food processor and run through a fine-mesh sieve. This removes the seeds and bits of skin and makes for a truly smooth real purée.
- If you had fairly watery tomatoes, you may want to put the purée back in the pot, bring to a boil, reduce the heat to maintain a simmer and cook to reduce it to the texture you want. Taste it along the way—you want a nice, bright tomato flavor.
- To chill or freeze: Transfer purée to sealable container(s) and chill or freeze until ready to use.
- To can: Bring a large canning kettle full of water to a boil. Sterilize the pint jars by boiling them for 10 minutes and allow to air dry. Soften the lids by simmering them for a few minutes. Put 1/4 teaspoon citric acid or 1 Tablespoon bottle lemon juice in each pint jar. Bring the purée back to a simmer, then fill each jar with hot tomato purée, leaving about 1/2-inch head space at the top of the jar. Set the lids on the jars and secure them with the rings. Lower into the canning kettle and boil for 35 minutes. Remove, let cool, and store in a cool dark cupboard for up to six months.