A great recipe from Charity Ferreira.
Toffee Popcorn with Cashews
If you do not have an air popper, just be sure to use popcorn without butter or additional seasonings.
Yield: About 9 cups popcorn
8 cups air-popped popcorn
½ cup (1 stick) unsalted butter, cut into chunks, plus more for pan
1 cup unsalted cashews (about 6 ounces), lightly toasted
1 ¼ cups sugar
¼ cup water
2 tablespoons corn syrup
½ teaspoon salt
1 teaspoon vanilla extract
Step 1: Place the popcorn and cashews in a large bowl. Lightly butter a 10-by-15-inch jelly-roll pan.
Step 2: In a medium saucepan over medium-low heat, stir together the sugar, ½ cup butter, the water, corn syrup, and salt until the sugar is dissolved and the butter is melted. Increase the heat and bring to a simmer. Cook, stirring occasionally with a heatproof spatula or a wooden spoon, until the mixture turns a deep golden brown (290˚ to 300˚F on a candy thermometer), 5 to 8 minutes. Remove from the heat and carefully (the mixture will bubble up) stir in the vanilla. Immediately pour over the popcorn and cashews and mix gently to coat with a spatula or spoon.
Step 3: Scrape the mixture out onto the prepared pan, spreading the popcorn out flat with an oiled spatula. Let it cool at room temperature until hard, about 30 minutes. Break apart and transfer to an airtight container. Store at room temperature for up to 1 week.