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When it comes to smokers, you can spend a lot of money buying one in a store. Restaurants will spend thousands on elaborate smokers. But you can make a backyard smoker out of just about any box, including cardboard.
First, you need a box no more than 4 feet (1.2 m) tall and 2 feet (0.6 m) wide. Cut a door in the bottom of one side to remove and reload wood chips during cooking. Next, insert two parallel dowel rods through the box at 12 and 36 inches (30 and 90 cm). You’ll place your racks (one pan to catch drippings and a wire rack to hold food) on top of the dowels.
Insert your heat source and wood chips into the bottom door. You can use a hot plate and wood chips in a cast-iron skillet, or similar arrangement.