Optional: Concasse tomatoes- scoop out stem of tomato. Using a sharp knife, slice an "x" into the other end of the tomato (this makes it easier to peel). Bring a large pot of water to a rapid boil.
Fill a large bowl with water and ice.
Dunk the tomatoes into the boiling water a few at a time and allow them to sit in the boiling water for about 2 minutes.
Remove and dunk in the ice water to cool.
This makes the tomatoes easier to peel, if you wish to peel them. It is totally optional, I don't mind the peels and I am lazy and hate to dirty every pot in the house, so I usually leave my peels on.