I prefer to spend a day making encaustic medium of melted, filtered beeswax and Damar Resin. Filtered beeswax comes in many natural colors.  This medium is the 'ground' applied on the birch panels.  I can use a particular color of beeswax, and create different undertone effects for a painting.  I brush and fuse three or four layers of medium on each panel.   I sometimes apply R & F White Encaustic Gesso as a 'ground' for encaustic painting on birch panels. I enjoy making different mediums; it's like stirring good pots of stew on a cold day.