Above is Daikoku-do, the building in which a ceremony called “Goma Hō” is held. You can read about this ceremony in this post. Daikoku-do is located between Kannon-do and Mie-do. You can visit the building to fill out a goma-ki.
Here is a better view of the altar used during the ceremony.
Every month at Ninna-ji on the 21st and the 28th a ceremony called “Goma Hō” is held inside of Daikoku-do. “Goma Hō” is a Buddhist rite which involves placing offerings into a fire. During the ceremony, a monk recites prayers while burning pieces of wood in a precise manner. Plain pieces of wood are placed into th fire along with pieces that visitors to the temple have written prayers upon. It is believed that the smoke from the fire travels to the heavens where it reaches the gods who will then grant the prayers. The ceremony is held at many temples and the prayers are directed to the principal deity of the temple.
If you visit Ninna-ji when this ceremony is being held, feel free to take a few pictures, but please keep in mind that it is a religious rite and be respectful! Loud talking and constant camera noises will distract the monk and are not very polite.