Bring about 2 quarts [liters] of water, enough to cover 1 or 2 of the tomatoes, to a boil in a small saucepan. Submerge the tomatoes 1 or 2 at a time in the boiling water and boil for 30 seconds. Drain them in a colander and rinse immediately with cold water. If you’re peeling a lot of tomatoes, use more water, cook about 10 tomatoes at once, take them out with a skimmer (again, rinse immediately), and wait for the water to return to a boil before adding more tomatoes.
While seeding is usually not necessary, there are times when you will want your tomatoes seeded: for example, when making sauces that aren’t being strained, or when using them in salads, where the seeds and the liquid that surrounds them can dilute the vinaigrette. There are two ways to go about it. The easiest way, best for sauces and baked tomatoes, is to cut the tomato crosswise in half and just squeeze the seeds out of each half. If you’re using tomato wedges in a salad, cut the tomato in half vertically and then cut each half into the number of wedges you want. Push the seeds out of each wedge with a finger.