Time needed: 45–60 minutes
- Kitchen scissors
- A box knife
- 50 feet of high-heat aluminum tape
- 30 feet of 18"-wide heavy-duty aluminum foil
- A sturdy cardboard box, around 14”x16” and 14” deep
- 4 empty aluminum cans (like soda cans)
- 4 - 6"x18" pieces of foil
- Sand or pinto beans
- Small grill
- Small metal cookie sheet
- Two stackable metal pie pans
- 8–12 charcoal briquettes
- Metal tongs or pliers
- Cookie dough
- Hot pad or pot holders
Setup: For this activity, you will want to go outside to a yard, your stoop or porch, or a rooftop. In order to cook something in your box oven, you will need hot charcoal. You can prep the charcoal using a fire starter in an empty coffee can, either in a BBQ grill or on cement—just be sure you are safe: be ready to handle hot coals with the tongs or pliers, and as with any fire, make sure you have your hair tied back and water close at hand.
- Starting with the top section of your box, cut open three sides of the box to create a fold-down top flap. This will be the “oven door.” Make sure to cut away from your body in case the box knife slips.
- Using extra cardboard wrapped in a double layer of foil, fortify the bottom of the oven, since this is where the heat is most intense. Then, wrap the entire box, inside and out, so each surface is completely covered with a double coat of aluminum foil, securing with tape. The shiny side of the foil will help reflect heat back into the oven.
- Now set up the inside of the oven. First, fill the cans 1/2–2/3 full of dried beans or sand. Then, tape the top of the can with a 2" piece of aluminum tape to make sure the sand or beans do not fall out. Wrap the cans with foil (optional) and secure with tape.
- Put the pie pans into the oven and arrange the cans around them in a square to hold up the grill. Set the grill on top of the cans.
- The box oven will get hot on the bottom, so be certain it is on a nonflammable surface outside. When the coals have been heated, carefully place them in the pie pans, using the tongs or pliers. Put your cookie dough on a small cookie sheet and carefully place it on the grill. Then close the oven door, but leave a small crack so there is plenty of oxygen for the coals. Heated coals supply 40–50 degrees each, so add as many as you need to make the correct cooking temp. Check the time or set a timer so you know when to check on the baked goods.
- When your cookies are done, take the cookie sheet out of your oven. Now you can sprinkle the coals lightly with water to help them cool off and set them in a safe place outside or in the BBQ grill to cool completely. The bottom of your box oven will stay hot for a while, so be careful if you move it directly after cooking.
As your food cools a bit, think about these questions:
- When or where do you think you’d use a box oven?
- What surprised you about this project?
- What are the biggest risks when using a box oven? And what do you think are the benefits?