I had them once, really liked them, I don't think I've seen them elsewhere now that I think about it though. St Louis had a number of things that were somewhat unique, toasted ravioli was popular there, basically fried ravioli, so like a mix between a cheesestick and ravioli, pretty solid gameday snack, and there was like a fried lasagna thing I think too, but I'm not sure if either originated there. I think toasted ravioli have started to expand more, never tried the lasagna thing so I never thought to look for it elsewhere
St Louis style pizza was an interesting too, it was pretty decent albeit not as good as NY style, or authentic, but it's hard to fuck up pizza outside of the big chain joints which do their very best.