A method of processing solid core ceramic matrix composite articles. The method improves the physical characteristics of the article by forming the airfoil using a co-processing method wherein a refractory ceramic is cast against a preformed ceramic matrix composite (CMC) shell. In one aspect, the shell is continuous to help prevent delaminations. In another aspect, the shell is open. In one embodiment, the article includes a split line. The split line helps the article to be less susceptible to damage caused from internal strain.