I seem to recall a religion that was fond of shambling mounds, I dont know if they just liked them or worshiped them. Does anyone know where I may be getting this from?
No clue. That being said, I'm sure many fantasy creatures are prone to finding worshipers. I mean, there's probably plenty of people who worship dragons, powerful undead, and maybe even certain magical beasts.
"Dungeon Denizens Revisited" contains several pages worth of Shambling Mound lore, but there's not much about anything like that. It does say that they on rare occassions coorperate with other intelligent creatures who can communicate with plants, and that they're sometimes venerated by intelligent creatures such as Lizardfolk, but that's about it. There's also a demon and a druid mentioned that each have large number of shambling mounds working for them.
In Forgotten Realms there were Moander - dead god or rot and decay. Pieces of his body functioning as mini-avatars of sort were divinely infused Shambling Mounds known as Bits Of Moander.
vegepygmy!