In a small saucepan, whisk together the half & half, milk, molasses, maple syrup, brown sugar, all the spices, and salt. (Save the vanilla extract for later)
Place over medium-low heat, whisking frequently until the mixture is hot and steaming — about 5 minutes. Avoid boiling; you just want to warm it enough for the sugars and spices to fully dissolve.
Once smooth and creamy, remove from heat and stir in the vanilla extract.
Let the creamer cool completely, then pour into a jar or bottle with a lid.
Refrigerate for up to 10 days, and shake well before each use — natural separation is normal.