What is Espresso? Espresso is a richly flavored, highly concentrated form of coffee that is brewed by forcing small amounts of pressurized, nearly boiling water through finely-ground coffee beans. Due to its method of preparation, espresso is generally thicker than coffee and it is served in shots with each shot measuring about an ounce. Espressos are usually poured into small, often white espresso cups known as demitasse cups.