The largest island in a lake on an island in a lake on an island (this is not a typo!) is the Vulcan point in Crater Lake on Vulcano Island in Lake Taal on Luzon (PHI)

Island in a lake

Also, the largest island in a lake on an island in a lake, is the Island in Mindemoya Lake on Manitoulin Island in Lake Huron (CAN)

Island in a lake

Do you want to see some more interesting Islands and Lakes?