In a medium saucepan set over medium high heat, bring apple cider to a boil. Reduce heat slightly and simmer until reduced to about 1/2 cup, about 10 minutes.
Add the brown sugar, butter, heavy cream, and cinnamon and simmer for 10-15 minutes until thickened, stirring frequently.
Remove from heat and stir in vanilla and salt to taste. Use immediately or store in the fridge for up to 2 weeks. Reheat in the microwave.
Calories: 1145kcal, Carbohydrates: 137g, Protein: 2g, Fat: 68g, Saturated Fat: 43g, Cholesterol: 204mg, Sodium: 360mg, Potassium: 429mg, Fiber: 1g, Sugar: 130g, Vitamin A: 2293IU, Vitamin C: 2mg, Calcium: 162mg, Iron: 1mg