After the core opens up, Flame Princess will ask you to go in and see what's going on. You'll need to pick up a bowl of fire and light the other bowls in the altar, but you can take the bowl outside to the camp near Cinnamon Bun and light the other braziers. If I remember, there are six in total, but the majority will be located near tents in this close vicinity. One will be near the Jake Trigger Point, but none will be beyond this little area.