If you've ever lamented St. Louis' lack of a proper Korean barbecue restaurant, your cries have been heard. Last month, Wudon (1261 Castillons Arcade Plaza; 314-628-1010) quietly opened in the Castillons Arcade Plaza in west county — and if the aroma of grilled meat wafting out of its front doors is any indication, the three week-old restaurant is well on its way to becoming the go-to place in town for authentic Korean cuisine.…