Warm the base: In a small saucepan, add the milk and cream.
Set over medium-low heat. You want it warm and steamy, not boiling.
Whisk in flavor: Add brown sugar, cinnamon, cream of tartar, and a pinch of salt. Whisk until the sugar dissolves and the mixture looks smooth.
Simmer gently: Let it heat for 2–3 minutes, whisking occasionally.
This helps the cinnamon bloom and the flavors meld. Do not let it boil.
Finish with vanilla: Remove from heat and stir in vanilla extract (and almond extract if using). Taste and adjust sweetness or cinnamon.
Strain (optional): For an ultra-smooth creamer, pour through a fine-mesh strainer to catch any cinnamon specks.
Cool and store: Let it cool to room temperature, then transfer to a clean jar or bottle.
Refrigerate.
Serve: Shake well before each use. Start with 1–2 tablespoons per cup of coffee and adjust to taste.