Get all your ingredients and tools ready before you start. You'll need a medium saucepan, whisk, measuring cups, and a jar to store your creamer.
Put 1 cup of brown sugar in your saucepan. Turn the heat to medium. Keep stirring the sugar until it melts completely into a liquid. Don't stop stirring or it might burn.
Once the sugar is melted, add 6 tablespoons of room temperature butter. Stir until the butter melts and mixes with the sugar. Let this mixture sit for 1 minute without stirring - this makes the flavor better.
Now comes the tricky part. Very slowly pour in ½ cup of heavy cream. Be careful because the mixture will bubble up. Keep whisking until everything is smooth.
Add 1 teaspoon of salt and stir it in. Take the pan off the heat and let your caramel cool down completely.
While you wait for the caramel to cool, get your storage jar ready. Once the caramel has cooled, pour 1 cup of it into your jar. Add 1 cup of heavy cream, 1 cup of milk, ¼ teaspoon of cinnamon, and ½ teaspoon of vanilla extract.
Mix everything together really well using an immersion blender or whisk until it's smooth. If you're using a whisk, make sure to mix for a few extra minutes to get rid of any lumps.
Taste your creamer. If you want it sweeter, add a bit more of the caramel you made. Keep mixing until you're happy with the taste.
Pour your finished creamer into a clean jar with a tight lid. It will stay good in the fridge for up to 2 weeks. Remember to shake it well before each use since the ingredients might separate.
To use your creamer, add 2-3 tablespoons to your coffee. You can add more or less depending on how creamy you like your coffee.