She's the one in charge of making the winner's brownie of the anti-fairies to fairies contest. She's also known to be as tough or more than Jorgen. She is a skilled cook and her chocolate brownies with cherries win every year's bake-off that determines which fairy species keeps the godchildren. Her recipe is very precious so she keeps it in a computer in a basement and if the camera there doesn't recognize her face, the vault will release weapons to hurt the intruder. She is also known for playing Explosive Bingo and doesn't like to be bothered while doing so. She also cooks explosive pies.
While never explicitly stated, Nana's physique and demeanor could be taken to imply that she was one of the harder-edged Battle Fairies of ages past.
Both physically and personality-wise, Nana Boom Boom's identical to her grandson, Jorgen (even their voices sound identical). The only physical difference between them is that Nana Boom Boom's considerably shorter than her grandson and has a slightly more feminine appearance. Jorgen feels it's hard to believe that he and his Nana Boom Boom are related.
Nana Boom Boom was first introduced in the episode, "Balance of Flour", where Timmy Turner and his fairies visited the Von Strangle family bakery, Strangle Buns, of which Nana Boom Boom is the current owner and where her grandson, Jorgen, works part-time.
She appeared again in "Cosmo Rules" and revealed to Jorgen that Cosmo and his family are actually distant cousins of the Von Strangle family. In that episode, it's also revealed that she enjoys playing Explosive Bingo, which Timmy is forced to play at the end of the episode as part of a punishment.
While she has never been directly addressed as "Nana Boom Boom Von Strangle", the name of her bakery would suggest she is indeed the mother of Jorgen's father. And if Nana, Jorgen and cousin Leonard's suggested physique are any indications, Jorgen's father would likely resemble them as well.
Nana Boom Boom has Jorgen's looks and voice, but her hair is in buns and she is noticeably shorter.
When she disappears she yells her surname and claps two explosive pies