Minestradi Morte
The Necromancer obtains a piece of a dead body and simmers it in a pot with half a quart of vampiric vitae. To this stew, the Necromancer adds rosemary (for remembrance), basil (the funerary herb) and salt (the alchemical principle of clarification). After bringing the concoction to a full boil, the Necromancer eats it.
If the ritual is successful, the caster can learn whether (or if) an individual became a spirito or spettro after death. Unfortunately, this information can be learned only about the person from who's body the "stew meat" was taken.
If the roll to activate this ritual is successful, the character discovers whether the subject of the grisly rite became a wraith or spectre after death, or if indeed she became either.
The blood component is spent progressively through the ritual. If the Necromancer takes the blood from another Kindred, she doesn't become partially bound from drinking it, nor does she add a point to her blood pool. Similarly, if she uses her own blood, her pool decreases by a point but does not increase when she consumes the soup.
Necromantic vampires without the Eat Food merit (see p. 296 of Vampire: The Masquerade) can't keep the soup down, but can still use the ritual and gain the information.
Reference: CGR 74
Note: While the ritual isn't specific, for the purposes of play, the ritual takes about 15 minutes in total and requires a full pound of flesh. "The Magister 18:40, 12 April 2016 (MDT)"
