width=398After Barbadian pop singer Rihanna tweeted a photo of a pack of rice cakes adorned with an earring and sunglasses, many are  asking the question: Was it a racist joke at the expense of Karrueche Tran, Chris Brown's half-Vietnamese girlfriend?

Karrueche Tran and Chris Brown are nominally girlfriend and boyfriend, but rumors have been flying since his musical collaboration with Rihanna that the controversial couple are back together.

It doesn't matter if they really are or not (and it's increasingly looking like they are): It seems that Rihanna is not pleased with Chris Brown's official girlfriend, model and socialite Karrueche Tran. Karrueche, who describes herself on Twitter as where Vietnam & the hood meet, and as half-Vietnamese, which is leading many to believe that Rihanna's recent tweet, accompanied by a photo of a bag of rice cakes dressed up in Karrueche's signature earrings and sunglasses, is a racist dig at Breezy's girlfriend. (Rice cake is a common epithet for those of Vietnamese descent, according urban gossip site Media Takeout.)

Gossip blogger Carlton Jordan also noted that the phrase is sung by Rihanna in the latest remix of Cake featuring Chris Brown: Remember how you did it? / Remember how you fit it? / If you still wanna kiss it / Come and get it / Sweeter than a rice cake, cake worth sipping / Kill it, tip it.

Chris Brown reportedly brought Karrueche Tran to Rihanna's Valentine's Day bash, but then made her wait in the car while he was inside. Why? In case he didn't get lucky with Rihanna.

In any case, Chris Brown and Rihanna being back together and Chris Brown and Karrueche still being together are not mutually exclusive scenarios. According to Radar Online, has told friends that [she and Chris] have an open relationship.