A solid cast block of water soluble detergent is dispensed by obtaining a solid detergent article of at least twenty liters cast onto a longitudinally extending structural core and placing the article within the spray chamber of a dispenser such that the article is supported on the structural core. The detergent article is then rotated upon the structural core while dissolving solvent is sprayed upon the rotating article. The resulting detergent solution is dispensed to an end use point.