4 cups apple cider (not juice)
1 cup granulated sugar
1/2 cup light brown sugar, packed
1 stick butter, cut into pieces
1/3 cup heavy cream
1/2 teaspoon ground cinnamon
1 teaspoon sea salt
1 candy thermometer
Pour the apple cider into a 3 quart saucepan and place on the stove over high heat. Bring to a boil, stirring occasionally, and let reduce until the liquid measures about 1/2-1/3 cup (this will likely take 30-45 minutes).
Meanwhile, measure out the sugars, butter, and cream and set aside. In a small bowl stir together the salt and cinnamon and set aside. Prepare an 8x8 inch baking pan by lining two strips of parchment paper on the bottom, leaving extra hanging off the top for easy removal once the caramel hardens. Set aside.
Once the apple cider has reduced, remove from heat and add the sugars, butter, and cream and stir to combine. Put back on the burner on medium-high heat and bring to a boil until the mixture reaches a temperature of 252 degrees F (about 5 minutes). Promptly remove from heat, stir in the cinnamon/salt mixture and pour into the parchment paper-lined pan. Let cool/harden on the counter (~2 hours) or in the fridge (faster).
Once hardened, remove the caramel by pulling up on the sides of the parchment paper and place on a cutting board. Using a well oiled sharp knife, cut into 1-inch squares and wrap in parchment/wax paper, twisting the sides to keep the caramel sealed. These will keep fresh for approximately 2 weeks on the counter. You can store them in the fridge, but I found them to be too hard when cold and just perfect when room temperature.