Leviticus 1:7-9

7The sons of Aaron the priest are to put fire on the altar and arrange wood on the fire. 8Then Aaron’s sons the priests shall arrange the pieces, including the head and the fat, on the wood that is burning on the altar.

9You are to wash the internal organs and the legs with water, and the priest is to burn all of it on the altar. It is a burnt offering, a food offering, an aroma pleasing to the LORD .