Heirloom Tomato Sauce

Kristine Kidd

Filled with the taste of summer, I make a couple of batches of this sauce at the end of the season when many farmers are selling large quantities of tomatoes at a discount and friends are overwhelmed with their home garden harvest. After the sauce cools, I spoon it into 1-quart freezer bags and freeze. We enjoy it all winter and spring, while waiting for ripe tomatoes the next summer. Pureeing the cooked tomatoes with an immersion blender eliminates the need to peel them, saving considerable time, plus the skins add good flavor and nutrition. Without an immersion blender, the sauce can also be pureed in batches in a countertop blender. Simmering the rinds of Parmesan cheese in the sauce adds complex richness. Whenever I finish a wedge of Parmesan, I save the rind in a plastic bag in the freezer or fridge, to add to sauces and soups.

Makes about 14 cups sauce (about 7 1-quart bags, each holding 2 cups sauce)

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Ingredients

¼ cup extra-virgin olive oil
2 large onions, roughly chopped
3 sprigs fresh rosemary
Coarse kosher salt and freshly ground black pepper
6 ounce can organic tomato paste
10 to 12 pounds heirloom tomatoes, cored, tough spots removed, cut into large wedges
3 to 4 rinds Parmesan cheese or Parmesan and Pecorino Romano
Generous handfuls of mixed fresh herbs such as basil, tarragon, thyme, marjoram and/or sage

Instructions

Heat the oil in a heavy large pot over medium-low heat. Add the onions and rosemary. Sprinkle with salt and pepper and sauté until the onions are translucent, stirring frequently, about 12 minutes.
Add the tomato paste and cook and stir for 1-2 minutes. Add as many tomatoes to the pot as will fit. Add the Parmesan rinds. Simmer, adding more tomatoes as the tomatoes settle down and make space. After all the tomatoes have been added, simmer uncovered until the tomatoes are very tender and mostly disintegrate and sauce thickens to thin tomato sauce (it will be thicker when pureed), occasionally stirring and breaking up tomatoes with spoon, about 2 hours.
Place the herbs on a cutting surface. Sprinkle with salt and chop finely. Add to the sauce. Simmer a minute or two to blend flavors. Let the sauce cool slightly. Discard cheese rinds, and rosemary sprigs, and then, puree with an immersion blender. Taste and adjust the salt and pepper. Let cool completely.
Mark a 1-quart freezer bag with date and “tomato sauce.” Place the bag in a large mug, glass or widemouthed canning jar and fold the edges over the rim. Spoon in about 2 cups of sauce. Place the filled bag flat on the work surface and coax out any air. Zip closed. Repeat with remaining sauce. Place bags of sauce on a baking sheet and freeze until firm. When frozen, the bags can be stacked. Thaw in the refrigerator before reheating and spooning over freshly cooked pasta.