English: Give me a break!

Spanish: ¡No Manches!

Type: Slang

Meaning: No way! Give me a break! Get outta here! No freakin’ way! Don’t fu***** do/say that!

Dude #1: Güey, tu novia me habló. Quiere salir conmigo.
(Dude, your girlfriend called me ... she wants to go out with me.)
Dude #2: ¡No manches, cabrón! (Yeah, right, ass****!)