“butter my butt and call me a biscuit” or “slap my ass and call me Sally” are colloquial expressions of surprise in the southern US.
according to wiktionary, another equivalent phrase is…
”dip me in honey and throw me to the lesbians”
The feminine urge to put this on a shirt, wear it, and then have someone take it literally, dipping me in honey and throwing me to the lesbians. Idk why, but the mere idea of someone getting coated in honey and then thrown to a crowd of lesbians sounds so absurd that I want to see it done in reality just for the absurdity of it