The recipe says Dutch-process cocoa. Can I use any cocoa powder?
Most recipes are formulate for either Dutched cocoa (acid neutralized) or Natural cocoa (like Hershey’s and Scharffen Berger), which normally requires something like baking soda, vinegar, or brown sugar to activate it. If using baking soda, an acid ingredient like natural cocoa powder is required to neutralize it to avoid a soapy taste. If one is specifically called for in a recipe, use what’s indicated. If not, I use Dutch process.