It explicitly outlines the various functions of the (*) kohanim and describes the construction of the Tabernacle under the direction of Moses.
The midrash of this book found in the Halakhah is called the Sifra. A portion of this book that was likely added later, its 27th chapter, discusses votive offerings and is read as part of Bechukotai. A section of this work orders the sending of a second goat into the desert to Azazel - that is the origin of the term "scapegoat."  This book relates the judgement of two brothers who offered a sacrifice with "strange fire," Nadab and Abihu. It explicitly outlines the various functions of the (*) kohanim and describes the construction of the Tabernacle under the direction of Moses. This largely consists of directions on how to conduct sacrifices in it, as well as various laws, such as a famous prohibition on homosexuality. For 10 points, name this third book of the Old Testament, known for its extensive collection of legal practices and offerings for the forgiveness of sins.
The midrash of this book found in the Halakhah is called the Sifra.
Book of Leviticus [or Vayikrah]