There is a drastic difference between baking and regular chocolate, especially when it comes to baking a cake. Baking chocolate is pure cacao , meaning no sweetener or flavor is added to the bar, making it very bitter. Many recipes that call for sugar, as well as chocolate, often call for baking chocolate. Because the cacao is so bitter, the particular added sugar in the recipe helps tone down some of that tartness while keeping the chocolate flavor. Then, you can control how sweet the final product is instead of risking it all by combining regular chocolate and sugar (via Hotel Chocolat ).
Regular chocolate bars contain many other ingredients in addition to cacao. Dark chocolate plus milk chocolate bars contain more than just cacao, making them enjoyable to eat, but not 100% like baking chocolate. Milk chocolate, for instance, is only required to have 10% cacao, according to U. S. law . The addition of ingredients, such as sugar, makes the end result sweeter than a baking chocolate bar.