Leonarda Cianciulli is known as "The Soap-Maker of Correggio".  Her oldest and favorite child Giuseppe Pansardi was getting ready to head off to war and she wanted to protect him.  She was a very superstitious woman who believed she needed to take a life, to save her son.  She murdered 3 women and turned their remains into soap and teacakes.   
Website: https://www.drinkingthecoolaid.com/  

Resources:

• Stregheria - Wikipedia
• Stregoneria – Wikipedia
• Benedicaria - Wikipedia
• The Deadly Soap-Maker of Correggio: The True Story of Leonarda Cianciulli a Superstitious Mother Who Turned Victims Into Soaps and Cakes (True Crime Explicit Vol 6) - Kindle edition by Ortiz, Genoveva, Seven, True Crime. Politics & Social Sciences Kindle eBooks @ Amazon.com.
• The Curse: A Shocking True Story of Superstition, Human Sacrifice and Cannibalism (True Crime) - Kindle edition by Green, Ryan. Politics & Social Sciences Kindle eBooks @ Amazon.com.