Concasse, from the French concasser, "to crush or grind", is a cooking term meaning to rough chop any ingredient, usually vegetables. This term is particularly applied to tomatoes, where tomato concasse is a tomato that has been peeled, seeded (seeds and skins removed), and chopped to specified dimensions. Specified dimensions can be rough chop, small dice, medium dice, or large dice.
The most popular use for tomato concasse is in an Italian bruschetta, typically small dice concasse mixed with olive oil and fresh basil, and sometimes other ingredients such as onion, olives, or anchovies.
Tomato concasse is also added to Béarnaise sauce to produce Choron sauce which is served with lobster dishes buttered.
References
Concasse Wikipedia(Text) CC BY-SA