The main drawback to the GSO, in my opinion, is that the interior is small and will only hold one pan. However, I have heard that many cooks get around this problem by stack cooking. Of course, that assumes that you have pots that will stack. I have two 3-quart granite ware pots that stack — kind of. They are supposed to stack, but the top one just barely does. Anyway, today I decided to give it a try. In the bottom pot, I put au gratin potatoes. In the upper pot, I put baked beans. Nothing too difficult. The top pot seemed to sit precariously, but it did stay put.
However, when I put the double stack into the GSO, I discovered that the double pot was too tall and the glass cover would not latch. The problem? Because it is wintertime, and the sun is lower in the sky, I had the back post up fairly high and the GSO angled to catch the best sun.
It was clear that the angle was causing the leveler tray to sway too far forward. So we lowered the back post down several notches until the double pot would fit into the oven. (That’s another problem. To raise and lower the post, you have to push in a little button into the post hole so that the inside post will move up and down. But it is very tight and I can not press the little button all the way into the hole. Rod has to do this for me.)
The oven still got plenty of sunshine and reached a temperature of about 300 degrees, enough to cook the potatoes and baked beans. But I think the oven would have gotten better sun, and therefore reached a higher temperature, if the angle had been higher.