The Collaborative International Dictionary
To rule the roast
Roast \Roast\, n. That which is roasted; a piece of meat which has been roasted, or is suitable for being roasted.
A fat swan loved he best of any roost [roast].
--Chaucer.
To rule the roast, to be at the head of affairs. ``The
new-made duke that rules the roast.''
--Shak.