It is forbidden therefore, by Biblical Law, to use the same utensils for both meat and dairy, as the taste might be retained and added to the item being cooked. It is also necessary to wait a certain period of time between the eating of the various types of foods. The duration of the waiting period depends on custom, which varies among communities, and also differs depending on the foods involved. It is forbidden to mix fish and meat as well, but this was instituted as a health injunction. However, they may be eaten in the same meal, as long as one washes out one's mouth and eats something between the two.
Some people have the same custom concerning fish and dairy.
And of course, all food must be cooked by a Jewish mother and applied in overabundance until you can no longer move. After which you must take home whatever hasn't been finished at the table.