Why do millions of people sit down to a meal of corned beef and cabbage? Because it's authentic Irish food...or so they think. Actually, only the cabbage is Irish. It's been a regular part of the Irish diet (along with potatoes) but was traditionally eaten with Irish bacon, rather than corned beef. When Irish immigrants came to America, they could not afford bacon, so they substituted it with a cheaper alternative they picked up from Jewish immigrants, corned beef.