A couple decades ago I took a cooking class at a canoeing symposium in Maine, and became enamored with reflector ovens. The instructor gave us plans for making our own. I made all three sizes and have been using them ever since, on canoe and float trips, for car camping, and in front of our wood stove during power outages.
I just stumbled across the plans again, so here you go.
These are not collapsible, but they don't take up much space because you can pack things inside them. They make great reflectors for your campfire even if you're not baking in them. And cinnamon rolls for breakfast and sourdough biscuits for dinner take camping food to a whole 'nother level.
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