Why Is McDonald's Hot Fudge So Good?

McDonald's hot fudge sundaes are a legitimate treat, one of the best desserts on their menu. And with 330 calories and 9 grams of fat, they're not that bad for you, either. But what makes them taste so good, exactly?

Here are the ingredients in McDonald's hot fudge topping, according to their website: sugar, water, sweetened condensed skim milk, hydrogenated palm kernel oil, nonfat milk, cocoa, corn syrup, salt, disodium phosphate, potassium sorbate, artificial flavor, soy lecithin, and polyglycerol esters of fatty acids.

Ignoring "polyglycerol esters of fatty acids" for the time being (we'd rather not even think about what those are), there's one ingredient lurking in there that might be the culprit for why McDonald's hot fudge is so good. That culprit is the sweetened condensed milk. One of a pastry chef's best friends, this is often the secret ingredient in lots of fudgy things, from dulce de leche to Key lime pie to, well, fudge. It's definitely something you should be baking with, if you aren't already.