Ah, espresso! It's been called the nectar of the gods and the elixir of energy. Properly prepared, the perfect shot of espresso is an unparalleled sensory experience, encompassing four of the five senses - five, if you include the sound of this delicious drink as it is prepared and consumed. A perfectly turned out shot of espresso is an incredibly refreshing hot beverage and has been termed 'the god shot'. There has been a great deal written about how to achieve a perfect shot/cup of espresso every time. Brewing the perfect cup of espresso consistently is a talent to which most baristas - both professional and at-home - aspire. What does it take to brew a perfect cup of espresso? Here are ten tips to help you make every shot of espresso a perfect shot.

1. Start with a clean machine. That should go without saying, but far too many people neglect the necessary maintenance needed to keep their espresso machines scrupulously clean. A film of coffee oils on your filter basket or group head can mar the flavor of your coffee, and mineral buildup in the various parts of the machine that hold and carry water can give your espresso a tinny or metallic flavor.

2. Choose the right coffee. It's not necessary to choose an 'espresso roast'; in fact, espresso roast is often darker than the roasts suggested for making espresso. Because espresso brewing extracts so much rich coffee flavor, you will get incredibly good results with coffee in the medium to medium-dark roast categories. Of course, you want to use GOOD coffee, but the variety is less important than the perfect grind.

3. The perfect grind is almost impossible to achieve with a cheap bladed grinder. The right grind for espresso is very fine, almost as fine as talcum powder. Aim for a grind somewhere between sugar and flour in consistency, and you will have it about right. You CAN get that consistency with a blade grinder, but you will generally 'burn' the coffee in the attempt. A burr grinder can be adjusted to exactly the right grind for espresso without damaging the flavor of the coffee.

4. Use the right amount of coffee. The "Espresso Rule of Thumb" calls for 7 grams of coffee for a single shot and 14 grams of coffee for a double shot.

5. Use good water. Filtered water is best for making espresso because you will leave behind all the little impurities that can affect the flavor of your coffee. On the other hand, distilled water can leave your coffee tasting a little flat. If you are lucky enough to have a semi-automatic machine with a built-in water filter, be sure to keep the filter clean.

6. Heat the water to the correct temperature. Espresso is defined as a coffee beverage brewed by forcing water heated to between 190 and 195 degrees through finely ground, packed coffee under high pressure. If the water is colder than 190, it will not extract enough flavor. If it is hotter, it can 'cook' the coffee.

7. Run a 'blind shot' through the group head before you make your shot to heat the group head to the right temperature. To make a perfect shot of espresso, the temperature should remain consistent all the way through the brewing time. If your group head is at room temperature, it can rapidly cool down the coffee right in the middle of the brewing process, resulting in weak coffee.

8. Tamp the coffee in the filter basket to pack it tightly. The "Espresso Rule of Thumb" says that you should get 1.5 ounces of espresso in 20-25 seconds. There are two major factors that affect how fast the water goes through your ground and packed coffee. The first is the pump pressure on your machine. The second is how firmly packed your coffee is. If the water is flowing through too fast or too slow, try adjusting either the grind of the coffee or the pressure that you use to tamp the coffee into the filter basket.

9. Use the right size tamper. This is a surprisingly simple solution that is often overlooked. If the tamper that you use is too small, the coffee around the edges of the filter basket won't be packed firmly enough. The water will take the path of least resistance through the coffee - right down the sides of the filter basket, missing most of the coffee flavor in your basket.

10. Use the right pump pressure setting. The correct setting for your pump pressure is 8-9 BAR.

Making perfect cup of espresso is not much different than making a perfect cake. Once you learn the recipe - which in the case of espresso includes pressure and temperature - you will be able to produce consistently excellent shots of espresso even when you start experimenting with different kinds of coffee.