Jess, regarding milk in yeasted breads (including Brioche), it needs to be powdered dry milk or if from a carton, boiled as per FreshKid’s instructions. There’s an explanation in the Bread Bible. Rose’s basic brioche doesn’t use milk, though some of the variations in the Brioche chapter in the Bread Bible do.
By the way, my avatar is Rose’s brioche, baked as a classic Savarin with rum syrup and strawberries- one of my absolute favorite things to eat!
Barbara, I was thinking we should do a “favorite way to use up extra egg whites” Bake-Off, I’m often in the same boat as you with extra whites in the freezer!