eat your ass with a spoon
You take a spoon, any spoon, and shove it up their butt so hard it makes a fart sound. Then you pull their guts out like spaghetti and eat it with the same spoon.
My mom said she'd eat my ass with a spoon if I didn't clean my room.
He challenged me to eat his ass with a spoon because he was full of hot air.
She ate my ass with a spoon during lunch and didn't even blink.