January and February are usually the slowest months for restaurants, which is why most of the restaurant week bargains tends to occur right now about now.
Irvine's Restaurant Week begins Friday, January 10 through Thursday, January 16, and it doesn't seem to have a hard and fast rule on what restaurants are actually in the City of Bren. Slater's 50/50 is technically in Lake Forest, and both Bluewater Grills (in Tustin and Newport Beach) are participating. But who cares so long as they're among the 37 restaurants offering bargains.
A handful of Diamond Jamboree restaurants like The Balcony and BCD Tofu House are also playing along, which is noteworthy because they usually shut themselves out of OC Restaurant Week.
So which one you gonna try? Check out the full list on the website and click on the offers linked. I, however, don't necessarily think the deal from Capital, the only one from my list of 10 Essential Irvine Restaurants, is as good as some others.