Turn on your oven to 200°F (93°C) and put three cups of popcorn in a heat-safe bowl in the oven. Line a baking sheet with parchment paper.
3 cups popped popcorn
In a wide frying pan, combine the sugar and water, stirring until the sugar dissolves. Heat the mixture over medium-low heat without stirring just until it turns a light copper color. It should not smell burnt.
½ cup granulated sugar, 2 tablespoons water
Remove the pan from the heat, and stir in the butter cubes, salt if your popcorn is unsalted, and one color of food coloring.
1 tablespoon butter, ¼ teaspoon salt, Gel food coloring
Quickly grab the popcorn from the oven and use a spatula to stir the popcorn to coat it with the caramel as much as possible.
Spread the caramel coated popcorn on your prepared baking sheet, breaking up large clusters with the spatula, and let cool completely.
Store in an airtight container with a food-safe desiccant packet for a durable crunch.
Food-safe desiccant packet