What do you think of Mosaic? (St. Louis)
I have not been to Mosaic but I have heard good things about it. Here is a past thread on the subject of Monday dinners in St. Louis-
I recommended Monarch in this thread and highly recommend it. Franco also gets lots of good reviews though I have not personally been there.
Franco serves on Monday; Monarch doesn't. Franco is a very good restaurant, generally highly regarded among the cognoscenti. Here's a very recent review by Joe Pollack: http://stlouiseats.typepad.com/st_lou....
If you need a complete list of the restaurants open on Monday, go to saucemagazine.com and use the advanced restaurant search engine.