What is a "Kosher kitchen"?

A kosher kitchen is one in which dairy and meat cannot mix. The kitchen includes two sinks that are ideally not in close proximity to each other.

A kosher kitchen also includes two dishwashers and two ovens in order to further prevent the mixing of meat and dairy. Sometimes a kosher kitchen has two refrigerators. Separate counters next to each dishwasher or sink are also ideal so that food can be prepared in a kosher fashion. Counter tops should be made from granite instead of porcelain or porous tile. The ovens in a kosher kitchen should also be self-cleaning so that they can be left on during the Sabbath hours, which are from sunset Friday to sunset Saturday.