What is the best of the best food plot to plant in Missouri?

It's tough to say what the "best" food plot is, no matter when you're planting it.  For me, it comes down to what sort of equipment and access I have to the location I want to put the plot, when I plan on hunting it (early or late), and how much maintenance I want to do.  When it comes to perennial plots, it's hard to be clover and chicory.  The deer love it, and it's relatively low maintenance so long as you mow it a few times a year to keep the weeds down.  Clover/chicory is great for early season through the middle of November.  For late season annual plots, I like radishes and purple top turnips.  The deer in my area love them, and they're not terribly difficult to plant.