Baking espresso powder usually refers to a soluble, dried coffee product used as an ingredient. It should not be confused with finely ground roasted beans intended for an espresso machine. CoffeeBox's guide highlights its convenience in chocolate cakes, brownies, buttercream and similar preparations where coffee flavour is wanted without a large increase in liquid.
Check the actual product and recipe. Espresso powder and instant coffee can differ in roast character and intensity, but there is no universal rule that one teaspoon of every espresso powder is stronger than every instant coffee. A small addition may complement chocolate without making coffee the dominant flavour, while a larger dose creates a clearer coffee impression.
Mix it with dry ingredients or dissolve it in a small amount of recipe liquid as directed. Replacing it with a brewed shot also adds water, so that substitution may require changing the recipe rather than pouring both in. Store the powder tightly sealed and dry. The ingredient still contributes caffeine; an unobvious coffee taste does not mean a dessert is caffeine-free.
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