Bring a small pot of water to a simmer. Meanwhile, score an X in the bottom of each tomato, just deep enough to cut the skin. Place the tomato in a slotted spoon and carefully lower it into the simmering water. Simmer for about 20 to 30 seconds, then remove with the slotted spoon to your work surface. Let it cool for a few minutes, then peel the skin off with a paring knife or your fingers, starting with the X. If the skin doesn't peel easily, submerge in simmering water for a few more seconds.