Measure your base: Add 1 cup whole milk and 1 cup heavy cream to a small saucepan. For a lighter option, use 2 cups half-and-half instead.
Sweeten: Stir in 1/3 to 1/2 cup brown sugar, depending on how sweet you like your coffee. Start with less; you can always add more.
Add spice: Whisk in 1 teaspoon ground cinnamon or drop in 1–2 cinnamon sticks.
Add a small pinch of salt.
Warm gently: Place the pan over medium-low heat. Whisk occasionally until the sugar fully dissolves and steam rises, about 4–6 minutes. Do not boil.
Flavor finish: Remove from heat and stir in 1 to 1½ teaspoons vanilla extract.
Taste and adjust sweetness or cinnamon now.
Optional smoothing step: If using ground cinnamon, blend the warm mixture with an immersion blender for 10–15 seconds to suspend the spice more evenly.
Strain (if desired): For a silky texture, pour through a fine-mesh strainer, especially if you used cinnamon sticks or want minimal specks.
Cool and store: Transfer to a clean glass bottle or jar. Let it cool, then seal and refrigerate. Shake before each use.
Use: Start with 1–2 tablespoons per 8-ounce cup of coffee and adjust to taste.
Great in iced coffee and cold brew, too.