AAVE slang derived from a brand of
sweet snack that’s similar to a vanilla wafer. It describes a light skinned Caucasian person. Depending on usage it can be said neutrally, cheekily, or condescendingly. It can have implications similar to the slang “vanilla wafer” referring to a person who is unadventurous. In that context “nilla wafer” suggests a person has little exposure to cultural media, customs, and cuisine
outside of their white racial experiences.