Stovetop espresso makers, also known as moka pots, are perhaps the one of the least popular styles of coffee maker. This may be due to the fact that they require a little bit of skill to brew delicious coffee. Just follow these six simple rules, and they will provide you with smooth exceptional coffee.

1. Don’t overfill the water reservoir. The lower chamber of a stovetop espresso maker holds the water that eventually gets heated and forced upwards through the coffee grounds. There is a release valve near the top of the water reservoir to allow steam to escape as the water begins to boil. Fill the water reservoir to just below the steam release valve. If the valve is covered, pressure will continue to build up until the moka pot explodes! This is a simple tip that will not only prevent bitter coffee, but also save you from a huge mess!

2. Use just the right amount of properly ground coffee. If you are grinding your own coffee beans, choose a grind that is finer than drip machine coffee but a bit more coarse than an espresso grind. Once you have the ground coffee, fill the coffee basket a little over two-thirds. Many instructions say to fill it to the top and level it off, but in my experience, filling the coffee basket all the way makes the brewed coffee taste bitter. Slightly under-filling the basket provides a much smoother cup.

3. Use good quality coffee beans. Obviously using better coffee beans will brew better tasting coffee. What may not be quite so obvious is which coffee is better. There are two common types of coffee on the market: arabica and robusta. Arabica is more delicate when it grows, yet overall has a much smoother flavor profile. Robusta is much easier to grow, as the name implies, but it typically has a sharper, more pungent taste. When buying coffee beans, choose arabica and you’ll get a more delicate brew.

4. Pick the right roast. The length of time the beans are cooked, or roasted, determines the type of roast. Roasts range from light to dark — the darkest roasts are referred to as Spanish, Italian, or French roasts. Darker roasts often have a slightly burnt taste. The type of roast you choose is personal preference. Remember that stovetop espresso makers brew strong coffee. So if you prefer a mild cup of coffee, be sure to choose a light to medium roast.

5. Use fresh, clean water. Don’t brew coffee with water you wouldn’t drink. Filtered water and spring water taste better than tap water, and so will your coffee if you use them. A side benefit of using filtered or spring water is that you’ll have less mineral deposits accumulating on your stovetop espresso maker, making it easier to clean.

6. Don’t let it cook. Listen carefully to your moka pot. When you hear a gurgling sound, your coffee is done. Take the stovetop espresso maker off the heat immediately. You may let it sit for thirty seconds off the heat if you want every last drop to make it into the upper chamber. However, if you leave the pot on the heat, your coffee will boil and take on a burnt, bitter taste. This is most crucial step in preventing bitter stovetop espresso.

A good technique is to time your stovetop espresso maker the first time you use it to find out how long it takes to brew a pot. Once you know how long it takes, set a timer for thirty seconds less than that time so you can be ready when it’s done brewing. Setting a timer will also prevent you from forgetting about your stovetop espresso altogether.

That’s it! If you follow these six simple tips for making smooth delicious stovetop espresso, you can’t go wrong.