Hot Egyptian soul piece (6)
I believe the answer is:
baking
'hot' is the definition.
(similar in meaning)
'egyptian soul piece' is the wordplay.
'egyptian soul' becomes 'ba' (term for the soul in ancient Egypt).
'piece' becomes 'king' (king is a kind of chess piece).
'ba'+'king'='BAKING'
(Other definitions for baking that I've seen before include "For putting bun in the oven" , "Extremely hot" , "Making bread, cake, etc." , "Making bread, cake or pastry" , "Making, eg, cakes" .)