What does the joke "go eat a sandwitch" mean?

[VeGaNiZeD wOrLd]

explain

 

[Facundo]

It doesn't matter as long as the sandwich you are eating is made of Enriquito Iglesias' salchicha, right, Ludito?

 

[Facundo]

It doesn't matter as long as the sandwich you are eating is made of Enriquito Iglesias' salchicha, right, Ludito?

 

[Emely.]

It means youre too retarded to figure it out.