Steaming tomatoes allows you to easily remove the skins for use in sauces, soups, stews and other recipes. You can also steam the tomatoes as a prelude to canning and other forms of preservation. The easiest way to steam your tomatoes is in an electric food steamer, which will also have specific directions for steaming different types of vegetables. If you do not have a food steamer, then a large pot with a steamer basket will work just as well.
Fill a large pot with one in. of cold tap water, or enough water to sit just below the bottom of the steamer basket. Add 1 tsp. of salt to the water, and bring the water to a boil.
Rinse the tomatoes with cold water. Pull off the green tops and cut an "X" in the bottom of each tomato with a paring knife.
Put the tomatoes upside down in the steamer basket. Put the basket inside the pot with the boiling water. The water should not reach into the basket.
Cover the pot and let the tomatoes steam for 3 minutes. Fill a large bowl with ice water, and put the bowl in a clean sink.
Remove the steamer basket from the pot. Dump the tomatoes into the ice water to loosen the skins, if your recipe calls for skinless tomatoes.