underfired

adjective2

1. •
   Fired at a low (or excessively low) temperature.

   • In terms of its body composition, Ru ware is essentially a slightly underfired (1200°–1250°C) stoneware with a high-alumina, low-iron clay of typical north Chinese composition. — 1999
2. •
   Of a cooker: having a heat source that is underneath the food being cooked.