1-Start by preheating your oven to 200°F (93°C) and lining 12×17-inch baking sheets with silicone mats or parchment paper for easy cleanup.

2-First, pop about 10 to 11 cups of plain air-popped popcorn and set it aside, making sure to remove any unpopped kernels.

3-In a medium saucepan over medium heat, combine the 1 cup (200g) packed light brown sugar, 1/4 cup (80g) light corn syrup, 1/2 cup (113g) unsalted butter, 1/2 teaspoon salt, and optionally 1/8 teaspoon cream of tartar.

4-Stir the mixture until it’s fully melted and starts simmering, which helps build that rich caramel flavor.

5-Once simmering, let the mixture bubble without stirring for about 4 minutes, until it reaches 234 235°F (112 113°C) for the perfect consistency.

6-Remove it from the heat right away and stir in the 1/2 teaspoon baking soda, which will make it froth up and create a lighter texture.

7-Quickly pour this caramel over your popcorn and mix everything evenly to coat each piece thoroughly.

8-Spread the coated popcorn onto your prepared baking sheets in an even layer.

9-Bake it in the preheated oven for 1 hour, stirring every 20 minutes to ensure even baking and prevent sticking.

10-Once done, let it cool for at least 30 minutes on the sheets so the caramel hardens and forms those tasty clusters.