Step 1
Start by preheating your oven to 250°F (120°C). Grease one large or two smaller roasting pans, then spread the popcorn evenly in them. In a medium saucepan over medium heat, combine the brown sugar, butter, corn syrup, and green food coloring. Keep stirring until the mixture comes to a boil, then let it bubble away without stirring for about 5 minutes. Take it off the heat and quickly stir in the vanilla extract and baking soda—the mixture will foam up a bit, but don’t worry, that’s normal. Pour this syrup over the popcorn and mix well to coat every piece. Pop the trays into the oven and bake for 45 minutes, giving everything a good stir every 15 minutes to make sure it cooks evenly. Once it’s done, stir the popcorn as it cools to break up any clumps, and you’re ready to enjoy!
