First Watch in Clayton, MO
I didn't think it was worth the wait. It's not bad, but it's not any better then a Bob Evans or a Cracker Barrel. The food was all under seasoned.
The best brunch I've had outside of a private club in St. Louis thus far, has been at Duff's.
The art museum brunch looks really good, but it's also quite pricey.
First Watch is mediocre at best, combine that with the Clayton airs it is very bad karma. I prefer the IHOP over First Watch.
Good diner type breakfast, go to the Majestic, not real fancy but good food. Or Courtesy Diner, that is a real greasy spoon, with slingers. Or Tiffany's or South City Diner.
For fancier breakfast/brunch, the Art Museum is good, it is a Wolfgang Puck operation. The history museum has the Patty Long brunch, which is very good too.