"rice cooker"
Actually it is original to the cooktop. Thermador called it the "Duo-cook". The pot is removable just like many other deep-well pots and the burner underneath lifts up for more burners. Sadly, it's only a 6" burner.
This is the cooktop I grew-up learning to cook on, except Mom's didn't have the Duo-cook. Ours had another 8" burner instead.