Bean Valley is an area that appears in Super Mario RPG: Legend of the Seven Stars.
Bean Valley actually has two parts to it:
Mario and his team venture into Bean Valley to continue on their quest. Eventually, they meet a Shy Away that starts to water many Piranha Plants. Mario and his team defeats them and eventually fight a much tougher Piranha Plant named Megasmilax. The oversized Piranha Plant is defeated and Mario heads up into the clouds and reach Nimbus Land.
Grate Guy's Casino Side-quest
Mario can actually get into Grate Guy's Casino through Bean Valley. He must jump down a Warp Pipe, defeat a Chain Chomp, and jump three times to make a platform appear and head into the casino. It is run by Grate Guy after splitting up from Knife Guy. Note, Mario must have the Bright Card in order to enter and Mario can earn one by playing Knife Guy's mini-game back in Booster Tower.
- Mario defeating the Megasmilax and heading up into the clouds is a parody of Jack and the Beanstalk.
- This similar to how Mario gets to the area to fight Huff N'Puff in Paper Mario.