The New York Deli, at 72nd and Troost in KC.
They've been in business (though not at that location) since Roosevelt was in office. Not Franklin, Teddy.
An "Awesome Ruben" indeed! Damn good Smoked Brisket or Pastrami too, plus walking in there when the morning baking is going on is an Epicurean delight.
A little pricey, but well worth it.
There is a German Deli over on Johnson Drive that is also fantastic, but the name escapes me.