Several principles have been proposed for the opposite of Occam's Razor, but they don't describe what I'm interested in, so here's mine:
The Believer's Hammer takes a simple solution and smashes anything that doesn't fit.
The easiest example comes from religion: Literalist Christians add up the Bible's years between Jesus and Adam and conclude God made the universe about six thousand years ago. Dinosaurs and carbon dating don't support their timeline, so the Hammer comes down: Dinosaurs died in Noah's flood, or God put dinosaur fossils in the Earth to fool nonbelievers, and carbon dating is a lie.
Secular beliefs rely on the Hammer too. Racists, sexists, and flat-earthers hammer away objections to their beliefs about race and sex and the shape of the earth. The Hammer simultaneously prevents testing of a belief while making its users think they're being critical as they swing their favorite tool.
We all start as hammer users; the luckiest of us learn to shave. My favorite examples are W.E.B. DuBois and Malcolm X, two men who looked at racism in America and saw skin privilege, then took up the Razor and saw capitalism underlying it. Had they been content with the Hammer, they never would've said things like these:
"...back of the problem of race and color, lies a greater problem which both obscures and implements it: and that is the fact that so many civilized persons are willing to live in comfort even if the price of this is poverty, ignorance, and disease of the majority of their fellowmen; that to maintain this privilege men have waged war until today war tends to become universal and continuous..." —W.E.B. DuBois, preface to The Souls of Black Folk, Jubilee Edition (1953, 50th Anniversary)
"I believe that there will be a clash between those who want freedom, justice and equality for everyone and those who want to continue the systems of exploitation. I believe that there will be that kind of clash, but I don’t think that it will be based upon the color of the skin." —Malcolm X
P.S. Another opposite principle for Occam's Razor: Procrustes' Bed. If it doesn't fit, rack it or hack it until it does.