How to season a character?

Question

Granny Bells, the Night Hag, has captured a PC (half-elf bard) and plans to eat her, as hags are wont to do. Granny Bells has a preference for sour and bitter food and an extensive array of monster parts and spices available for her cooking adventure. She's originally from Chult, but has since moved to Barovia, so she has access to ingredients from the Tomb of Annihilation campaign and the Curse of Strahd campaigns, as well as all items listed in the core rulebooks.

What should she throw into her cauldron along with the half-elf to get as sour and bitter a half-elf-soup as she can manage?

The ingredients must be:

• Actual cooking ingredients listed in one of the 5e rulebooks or the Curse of Strahd or Tomb of Annihilation adventure modules, described as especially bitter or sour

or

• Part of a monster from a 5e rulebook or the Curse of Strahd or Tomb of Annihilation adventure modules, described as especially bitter or sour. Granny Bells is not particularly concerned about the ethics of killing sentient monsters to prepare her food. (Obviously.)

All ingredients must also be edible for a hag. Assume the hag can eat essentially anything that is not made of rock/metal. Poisons and such do not bother her, but she's not going to eat a sword.

A required ingredient is a half-elf, obviously, but she's got that part covered. Granny Bells is not well versed in cooking and operates under the assumption that more ingredients is better, so the best answer will be the one that throws in the most bitter and sour ingredients. She'll get a bigger cauldron if need be.

Answer 1

There are mentions of possible bitter ingredients in ToA:

• Sinda Berries:

  These berries are dark brown and bitter

• Assassin Vine's fruit:

  The fruit is tough and has a hearty but bitter flavor.

Curse of Strahd does not seem to have anything specifically called out as being bitter or sour, nor could I find other references within your constraints to possible bitter or sour ingredients using D&D Beyond search

Answer 2

Depending on a DM's interpretation, Xanathar's Guide to Everything provides an item that might take care of this all by itself - Heward's Handy Spice Pouch (p. 130):

While holding the pouch, you can use an action to expend 1 of its charges, speak the name of any nonmagical food seasoning (such as salt, pepper, saffron, or cilantro), and remove a pinch of the desired seasoning from the pouch. A pinch is enough to season a single meal.

It has 10 charges, and regains 5-10 each day, so it can certainly handle several seasonings in one meal.

This leaves two big questions which would require adjucation.

1. Firstly, is the stew this hag makes in her cauldron "a single meal"? That might depend on whether she eats it all at once, perhaps.

2. Secondly, does any natural ingredient which is typically used for flavoring count as a "nonmagical seasoning"?

   If both of these answers are judged to be "yes", then the Handy Spice Pouch can provide a cauldron's worth of various flavors - anise, rhubarb, wormwood extract, persimmon juice... As well as anything particular to Faerun or Barovia.