There are times when it might be necessary to find a substitute for bittersweet chocolate. It could be because of dietary needs or lack of stock at a store. Either way, it is possible to use a substitute for bittersweet chocolate. Semisweet chocolate can be used instead, although the taste of the finished product might be a bit different. Unsweetened chocolate can be added, as can cocoa powder, if some type of fat also is used.
Bittersweet chocolate is defined as containing less than 35 percent chocolate liquor, the highest amount of most chocolates available. It also has milk solids in it. Semisweet chocolate is the closest product to bittersweet, although the taste will be slightly sweeter because of the manufacturing process. Semisweet chocolate also tends to have less chocolate liquor in it than bittersweet.
One good substitute for bittersweet chocolate is dark chocolate, often available in candy bar form and in the baking section of many grocery stores. The actual composition of bittersweet chocolate is technically dark chocolate, although there is no formal definition for the content of dark chocolate. Extra dark chocolate, available in the baking section of many supermarkets, also can be used.
If there is nothing else available, then milk chocolate can be used in a pinch. It has a high amount of milk solids in it and a low amount of chocolate liquor, which means it will taste very different from bittersweet chocolate. If being used on its own as a filling or topping, it might be an acceptable substitution; if it is being used as part of a recipe in which it will be melted and mixed with other ingredients, then it might not be a suitable substitute for bittersweet chocolate.
Powdered cocoa can be used as a substitute for bittersweet chocolate if it is mixed with water and has a little fat added to it. The powder needs to be bloomed in some warm water before being added and then poured in with some butter, oil or shortening to make up for what would have been in the bittersweet chocolate. The taste will not be quite the same, and the recipe might need additional sugar. In the end, however, there will still be a distinct chocolate taste.
If the reason for finding a substitute for bittersweet chocolate is because of a diet free of carbohydrates or animal products, then carob could be an option. Carob looks like bittersweet chocolate, but it has a different flavor. It can work like bittersweet chocolate in most recipes. A piece of carob should be tasted before adding it to a dish to ensure that the flavors will work together.