what does this mean ?

So I posted a picture on my instagram of a Oreo chake saying "cravings 😋😋😋😍" and my cousins gf comment and said " Aawww i think there's a cake in a bun ." What does she mean by that ?? 🤔🤔😵 I'm hoping it's not what I'm thinking I have never heard some one say this so that's why idk what she means by this and my boyfriend got mad and said to delete it so I deleted the picture any one has heard of that or know what she's trying to say ?