To make it thinner, add a little light corn syrup.
You could add cocoa to it to make it chocolate, if desired. I also added a drop or two of almond extract to take away some of the sweetness, but it's fine without it, too.
Substitutions
Butter and Margarine: Butter is a dairy product made from cow’s milk. Margarine typically contains milk or soy, but there are milk-free and soy-free versions available.
Corn Substitutions: Corn is a common ingredient in products. Starch, modified food starch, dextrin and maltodextrin can be from corn. Consult with your physician to find out which corn derivatives you need to avoid. Many corn-free options are available in the US. Find out more about corn substitutions.
Milk and Soy Substitutions: Alternative dairy-free milk beverages and products will work in most recipes. Find out more about milk substitutions and soy substitutions.