cauldron

kattila, pata A large bowl-shaped pot used for boiling over an open flame.
1623, William Shakespeare, http://en.wikisource.org/wiki/The_Tragedy_of_Macbeth Macbeth, Act IV, Scene I:

Double, double toil and trouble;

Fire burn, and cauldron bubble.

(�) I don't expect you will really understand the beauty of the softly simmering cauldron with its shimmering fumes, the delicate power of liquids that creep through human veins, bewitching the mind, ensnaring the senses … (�)

Large cauldrons are a little tricky to locate, but are well worth the search if you have a place to safely store and use one.