Onboard Cookie-Baking Trick
Galley ovens often have hot spots. The short distance from the flame to the pan, a small heat shield, and the smaller volume of air inside the oven all contribute to food burning on the center bottom before its outer edges are cooked through.
A baking stone (also called a pizza stone) does wonders to even out the heat. It should be sized so there is an inch of space on all sides for air flow (a tile shop can cut a stone down if necessary). Also, stones that are at least half an inch thick are much less likely to crack when heated.
Place the stone on the oven rack.
I use all-metal binder clips on the rack to keep it from sliding around and I leave it permanently installed in the oven. As the oven preheats, the stone warms up evenly and holds heat so that air in the oven quickly warms back up after you open the oven door. Place your pan on top of the hot stone and bake as usual. Never put a cold pan on a hot stone and never let liquid spill on a hot stone—both will cause it to crack.