What prohibitions exist regarding cooking meat and dairy?

Three prohibitions regarding meat and dairy: (1) Eating: you may not eat meat and dairy together in any form, (2) Cooking, you may not cook them together even if you won't eat the result, (3) Benefit, you may not sell or otherwise profit from a meat-dairy mixture. These prohibitions apply to the meat of kosher mammals and birds with milk of kosher mammals. Fish with dairy is permitted by most communities (though some Sephardic customs restrict fish with cheese).