Caramel Popcorn - vegetable oil

Method

• Pop the popcorn:
• Spray two large heatproof rubber spatulas and a very large metal bowl (at least twice the volume of the popped popcorn) with nonstick cooking spray, or lightly wipe with vegetable oil.
• Heat the oil in an 8-quart or larger heavy-based stockpot over high heat.
• After a minute, put a popcorn kernel in the pot and cover.
• When the kernel pops, the oil is hot enough.
• Add the rest of the popcorn kernels.
• Cover the pot and shake it back and forth over the heat to agitate the kernels.
• Keep moving the pot as the popcorn pops.
• Remove the pot from the heat when the popping slows almost to a stop (its better to have a few unpopped kernels than burnt popcorn) and immediately pour the popped corn into the large metal bowl.
• Search through the popcorn, removing any unpopped kernels (which fall to the bottom of the bowl) or burnt pieces.
• Make the caramel:
• Measure the baking soda into a small dish so its ready to go.
• Line two rimmed baking sheets with parchment, foil, or nonstick silicone mats.
• In a 4-quart or larger saucepan, combine the sugar, salt, butter, and 1 cup water.
• Gently stir with a wooden or metal spoon just enough to immerse the sugar.
• Brush down the sides of the pot with water and a clean pastry brush.
• Cook the sugar mixture over high heat without stirring until it melts and bubbles and turns a very light golden caramel color on top; this will take 10 to 20 minutes, depending on your stove.
• The caramel will be darker than it appears on the surface, so dont overcook.
• At this point, remove the pot from the heat.
• Working quickly off the heat, thoroughly whisk the baking soda into the caramel.
• Do this in or near the sink in case it spills over.
• The baking soda aerates the cararmel, which makes it easier to eat when its cool, but causes it to bubble vigorously now, so be careful.
• Immediately pour the bubbling caramel over the popcorn in the bowl.
• Only use the caramel that pours out easily; dont scrape the sides of the pot (the sugar on the sides of the pot crystallizes easily and can cause the caramel to do the same).
• Using the heatproof spatulas, toss the caramel with the popcorn.
• When the popcorn is thoroughly coated, pour it onto the lined baking sheets and use the spatulas to pat it into one flat layer.
• As soon as its cool enough to touch, use your hands to break the layer into smaller clusters.
• Let them cool completely and then store in an airtight container for up to a week.