• Instant coffee (preferably a dark roast) – Because instant coffee isn't as rich as espresso, you may want to increase the amount called for in the recipe. Faith notes that you can use about 50% more but be aware that it "has a harsher taste than instant espresso [and] can taste tinny or sour if too much is used."
• Brewed espresso – Using liquid espresso may require adjusting the other ingredients in your recipe. As Emma advises, "be sure to subtract the amount of coffee or espresso being used from the overall liquids in the recipe."
• Espresso grounds – According to Fine Cooking, commercial espresso powder is actually made from espresso beans that have been ground, brewed, dried, and then further ground. We recently tried this at home to make Martha Stewart's Mocha Slice Cookies and although the process was a bit time-consuming, our homemade powder actually worked very well. We used a mortar and pestle to crush the grounds into a very fine powder.
Have you used any of these substitutes – or another? How did it work for you?