What is the origin of the phrase "in a pickle"?

The Middle English word Pikel meant "a spicy sauce or gravy served with meat or fowl" as early as 1400. The middle Dutch word pekel referred to a solution, such as spiced brine, for preserving and flavoring food. After it came to the English language, the connotations of the word expanded to include brining for preservation, and to the ingredients that had been treated or transformed in the brine. The Dutch phrase in de pekel zitten, "sit in the pickle," probably gave rise to the figurative meaning of being "in a pickle" as being in a difficult or problematic situation. Modern slang adopted "pickled" as a synonym for drunk.

http://www.nyfoodmuseum.org/_pkwhat.htm

Meaning: In a quandary or some other difficult position.

Origin: This alludes to the pickling liquid made from brines and vinegar which is used to preserve food, and presumably to the imagined difficult of being stuck in such. The phrase was known in Dutch by 1561 - ' in de pekel zitten' meaning 'to be in a pickle'. There are a few references to ill pickles and this pickle etc. in print in the late 16th century, but Shakespeare appears to be the first to use in a pickle, in The Tempest.

https://www.phrases.org.uk/meanings/in-a-pickle.html