Milled tomatoes are the gift that keeps on giving. They're the key to Martha's Simple Marinara, and the scraps make a delicious Summer Tomato Water.
Blanch: Prepare an ice bath. Bring a pot of water to a boil. Score a shallow X in the bottom of each tomato with a knife, then place in boiling water for about 10 seconds. With a slotted spoon, transfer tomatoes immediately to ice bath.
Peel: When cool, remove and peel tomatoes by gripping the skin between your thumb and the flat part of a knife blade, starting at the scored X.
Seed: Quarter tomatoes lengthwise and scrape out seeds with your fingers or a spoon. Reserve seeds and juice for Summer Tomato Water.
Mill: Pass tomatoes through a food mill fitted with a fine disk, removing pulp as it accumulates. Stir in kosher salt to taste. Portion into jars, leaving 1/2 inch of headspace, and freeze until ready to use, up to 1 year.