I would always just rephrase, and DD would repeat.
At 3, it was something like:
"Mommy! PIZZA! MORE PIZZA!"
"More pizza, please, Mommy?"
"More pizza PLEASE MOMMY!"
She sound exasperated with it every time, but now all I need to do is "the look" and she rephrases most times.... but she's also 10 now, LOL.
--Mimi
Mom to Lala (2004), Bonus Mom to Big Sis 1 (1991) and Big Sis 2 (1992)
Grammy to Big Kindy Kid (2011), Big Pre-K Kid (2012),
Grandbaby Appendage (2014), and New Baby Grandboy (summer 2017)