The first step is to set up a double boiler or create one by adding a pot filled about a little bit with water and place a glass or heat safe bowl on top.
Next, add all of the ingredients except for the essential oils to the glass bowl and over medium low heat, bring the water to a low simmer.
Mix the ingredients well while they are warming up. Once they are completely incorporated, very carefully remove from heat. Stir in essential oils if using them.
Using potholders, very carefully pour the hot liquid into your storage container of choice.
Allow to cool completely and place a lid on for storage.