To grind or mix thoroughly: Pulverise. (Merriam – Webster)
Think about (a fact, proposal, or request) deeply and at length. (Oxford Dictionaries)
To heat wine or beer with added sugar and spices. (Cambridge Dictionary)
If you mull something, you think about it for a long time before deciding what to do. (Collins Dictionary)
Phrasal verb. Mull over.
How long does it take to mull something over?