Up in the ice levels you will come across a weird structure made of stone that accepts an item from your inventory. The message on the sign post that will tell you to insert a flower that glows in the dark.
So what does this mean? You will need to find a cinderbloom and place it into the structure in order to activate it. There are a few ways you can find these. The easiest is to go to the desert temple. There are 3 or 4 of these flowers inside this temple and since it is close to the starting square, you will more than likely have unlocked and completed this temple already.
Once you place the flower, a chest will appear and the puzzle will be solved.