~from Savoring Time in the Kitchen
This makes about 1-1/2 tablespoons of espresso powder.
If you have an espresso maker at home, after brewing a double shot, save the grounds or ask your barista to give you the grounds after you order your next espresso drink at your coffee shop.
Spread the grounds on a small baking sheet and spread them out to dry.
Preheat the oven to 300F and place the baking sheet in the oven and allow the grounds to toast for 30 minutes.
Allow the ground to cool and pulse them in a coffee/spice grinder until finely ground.