Fantasy fairy illustration with a classic witch's cauldron: a huge rounded black cast-iron cauldron with a wide thick curved rim, bulging sides, three short curved legs and two side handles — clearly recognizable as a traditional witch's cauldron. Two young adult beautiful witches are inside the cauldron and washing it from the inside. Each wears a high pointed witch's hat with a wide brim, a ribbon and magical symbols. They hold large soapy rags and scrub the cauldron walls covered with shimmering green, purple and blue remnants of magical potion. Thick soapy foam drips from the rags. At the bottom of the cauldron is a thin layer of water with white foam and bubbles. The witches' skirts and aprons are wet, but their clothing is modest and fully covered. A magical workshop, soft magical lighting, sparks and bubbles, dynamic composition, detailed fantasy concept art illustration, no text or logos.