Exodus 29:31

And this is the thing that thou shalt do unto them to hallow them, to minister unto me in the priest's office: Take one young bullock, and two rams without blemish,

And unleavened bread, and cakes unleavened tempered with oil, and wafers unleavened anointed with oil: of wheaten flour shalt thou make them.

And thou shalt put them into one basket, and bring them in the basket, with the bullock and the two rams.

And Aaron and his sons thou shalt bring unto the door of the tabernacle of the congregation, and shalt wash them with water.