The line comes from Fat Bastard, the gluttonous Scottish villain played by Mike Myers in Austin Powers: The Spy Who Shagged Me from 1999. In the film, his obsession with food and his distinctive accent turned a simple demand into one of the character's most quoted lines. As clips from the movie circulated on early soundboards and later in meme edits, the misspelled version get in mah belleh stuck as the way fans write it online. It remains popular because the joke is instantly clear even without seeing the film.