Ever have a cookie and it just tasted bland or flat? Something was missing? The most common problem I’ve found with cookies is when unsalted butter is used in a recipe just just calls for “butter”.
Why is this a problem? Well, most recipes that call for butter expect a certain amount of salt to come from the butter. And, unless you adjust the recipe and add additional salt when substituting, your recipe will come out very bland. Believe it or not, salt is necessary in baked goods, not just in how the cookies react, but also in taste. A certain amount of salt will add that extra YUM factor. (of course too much salt and you go from YUM to YUK!)
You will find that many commercial bakeries and restaurants will make their recipes with unsalted butter so that they can control the amount of salt going into their baked goods as there is no requirement as to how much salt is put into butter. Different manufacturers may put in different amounts. The rule of thumb when substituting is 1/2 tsp salt per 1 cup of butter.
So, now you know to be careful when using unsalted butter and to adjust the recipe if needed.