To peel tomatoes, cut a shallow X in the bottom end of each one. Immerse the tomatoes in a pot of boiling water and blanch for 15 seconds. Using a slotted spoon, transfer them to a bowl of ice water to stop the cooking. Then use your fingers or a small knife to slip off the skins. To seed tomatoes, slice them in half crosswise (across the equator). Hold each half over a sink or bowl and lightly squeeze and shake it to dislodge the seeds, using your fingers if needed.