You would need to gather:
A cardboard box (medium size)
1 roll of Reflective tape
1 Foam Board
The rest of the materials are:
1 roll of Duct Tape
Pot or pan
1 roll of Aluminum Foil
7 feet of string
Tools you will need are:
The materials themselves cost about ten dollars. The duct tape was about four dollars, the aluminum foil costs a dollar from the dollar store, the reflective Mylar costs a dollar per yard, the foam board was free due to reusing from a conference (if you can't find the foam board use cardboard. It took about a hour and a half to assemble this project. The dimensions of the final project is the height being .You only need to get sunglasses in order to not hurt your eyesight. Also, be cautious of the box cutters they are very sharp. You can substitute the foam board for cardboard and you can substitute the reflective tape with silver duct tape it doesn't work as well but it still works.
Step 1: Step 1: Box (ugly to Woah)
You get a normal (BBB) big boring box. Then you take apart the parts of the box that glues it together to form the shape that will bring in the most sunlight.
Step 2: Step 2: YAAASSS Duct Tape.
ONce you get the angle that you think or have calculated would be the best you tape that box. Not with the mediocre tape that sucks but use duct tape. The best known tape to human existence. Make sure there is enough that even a gorilla wouldn't be able to destroy it.
Step 3: Step 3 : Board Cutting Time.
Then Grab a large board. It doesnt matter what kind as long as its flat and you could put stuff like fill and tape on top of it and it would be able to stay smooth. Try to not mess up and outline it like they make kids do in the 5th grade. It will be extremely helpful. No one likes wasting big boards of paper or whatever.
Step 4: Step 4: MORE Duct Tape and Connecting Two
Once the outline is done cut the piece out with a knife. Then put duct tape on the base of the box and put the cut out piece of the board on top of it.
Step 5: Step 5 : Aluminum ALL OF THE THINGS!
Put aluminum foil and aluminum tape to use for the base because it would not be used as much to collect sunlight. The walls of the box are what will be bringing in the most sunlight. For the walls use reflective Mylar It sounds cooler and works better.
Step 6: Step 6 : Outgoing Box
Once you are all set building the solar thermal cooker adjust it so that it would get a lot of sunlight to heat up the food that you would want to cook. You should also use a black pot to absorb the heat other then the other loser crom pots that stink. It would also be helpful to have a shadow creature to guard your cooker. We used a magestic shadow horse. It help IMMENSELY.