The Pasta Machine is a synonym for ass, you can produce shit with yo ass, so u can produce pasta withe the Pasta Machine, since both are produced in the ass/Pasta Machine its equals the same so it is like Shit is the same as Pasta. It also can be used as a compliment.
see in the example
1) Joe: Dude, i ate PASTA the whole night.
Robert: WTF, this is gross dude.
2) You: Nice Pasta Machine.
Girl: ehhhm, thanks i guess.
(She dont know what u mean, except if has read this )