Complex sentence: The world's most expensive pizza listed by "Guinness World Records" is a seafood pizza called the "C6" that is prepared at Steveston Pizza Co. restaurant in Steveston, British Columbia (in the Metro Vancouver area) which costs $450 Canadian dollars.
Split into simpler sentences: The world's most expensive pizza is said to be the seafood pizza called the "C6" that is prepared at Steveston Pizza Co. restaurant in Steveston, British Columbia (in the Metro Vancouver area). It is listed by "Guinness World Records" as the world's most expensive pizza, and costs $450 Canadian dollars.