For best results, you should follow a recipe exactly as written. If you need to make an emergency substitution, you can successfully substitute cocoa powder for semisweet chocolate in most recipes. Dutch-process or alkalized cocoa powder has a mild flavor. On the other hand, natural unsweetened cocoa powder has a stronger, slightly bitter flavor. Both types of cocoa powder can serve as a substitute for chocolate when combined with the proper ingredients.
Determine how much semisweet chocolate is included in the recipe. For each ounce of semi-sweet chocolate, you need 1 tbsp. plus 1 3/4 tsp. of cocoa powder, 1 tbsp. plus 1/2 tsp of granulated sugar and 1 1/2 tsp. of melted butter, shortening or margarine.
Dissolve the cocoa powder in at least 1/4 cup of hot liquid from the recipe, to enhance the chocolate flavor.
Add the granulated sugar to the cocoa mixture. Stir the mixture until the sugar is completely dissolved.
Add the melted butter, shortening or margarine. A light cooking oil can also be used, but this will affect the texture of baked products. Stir until well incorporated.
Use the cocoa mixture as a replacement for semisweet chocolate.