In terms of time, 4.5 hours is enough to get to the Forbidden City. We can have a meal at noon and then go to the Marshal's Mansion.

If your money allows, you can just eat at Dashuai Mansion. It has many specialties but I have never tried it.

Either go to Laobian Dumplings or go to Europa.

If you want to eat casually, it doesn't matter where you go. There are also places to eat in big shopping malls.