If it called for baking chocolate, either semi-sweet or unsweetened, I bought the baking chocolate.
I have since learned ways of making my recipes without having to rely on buying squares of baking chocolate.
Many people believe that using cocoa powder instead of unsweetened baking chocolate will actually make the food taste more chocolaty.
It certainly makes it easier and it always turns out yummy.
To change the recipe from chocolate squares or ounces. use 3 Tablespoons cocoa powder plus 1 Tablespoon cooking oil, shortening, or butter for every ounce or square of unsweetened chocolate.
If you want semi-sweet chocolate, add 1 Tablespoon sugar to unsweetened chocolate. To get a cup of semi-sweet use 9 Tablespoons cocoa plus 7 Tablespoons sugar plus 3 Tablespoons oil, shortening, or butter.
Another great way to get semi-sweet chocolate is to use chocolate chips. 3 Tablespoons of chocolate chips is equal to one ounce or square of chocolate. When a recipe calls for 6 ounces, you will need a cup.
I have not bought any semi-sweet or unsweetened baking chocolate in many years.
I have never had any problems cooking or baking by substituting cocoa powder and cooking oil or by using chocolate chips.
I love using oil over shortening or even butter. Since it is in liquid form, you don't have to melt it.