This is the single most genius thing you can do to a tomato. They’re best and most outrageous when made with ripe Romas or other meaty types, but as Wizenberg points out, slow-roasting will bring out the tomato in even the pale and off-season, if you feel the need. Make a lot. They keep for a week in the fridge, and are just fine in the freezer. Adapted slightly from Orangette and A Homemade Life (Simon & Schuster, 2009). —Genius Recipes
Heat the oven to 200° F. Wash the tomatoes, cut out the dry scarred spot from the stem with the tip of a paring knife, and halve the tomatoes lengthwise. Pour a bit of olive oil into a small bowl, dip a pastry brush into it, and brush the tomato halves lightly with oil. Place them, skin side down, on a large baking sheet. Sprinkle them with sea salt and ground coriander—about a pinch of each for every four to six tomato halves.
Bake the tomatoes until they shrink to about 1/3 of their original size but are still soft and juicy, 4 to 6 hours. Remove the baking sheet from the oven, and allow the tomatoes to cool to room temperature. Place them in an airtight container, and store them in the refrigerator.