- Cut out three sides of a square on the pizza box lid, about two inches from the sides.
- Fold back the flap you just made and cover the inside with foil (shiny side out), taping it in place.
- Open the box and cover the bottom and sides with foil.
- Cover the hold in the box lid that the flap made with plastic wrap, taping it in place.
- Put food on a paper plate and place it inside the box on the foil bottom.
- Close the lid, fold back the flap and prop it open with a ruler. Put the box outside, with the flap facing the sun. Be patient! It may take an hour or longer to heat up your food.
Check out this document for some additional visual instructions.
The sun's light rays are collected by the foil flap and concentrated inside the box. The rays are transformed into thermal energy that slowly raises the temperature inside the box, causing the food to cook.
The solar cooker can get very hot, so use caution when handling.