The coffee makers that brew the strongest cup of coffee are the AeroPress Coffee Maker and the Chemex Classic. The AeroPress focuses more on creating strong and smooth tasting espresso beverages that can really give you a kick. The Chemex Classic can make some strong coffee without bitterness thanks to the thick filters it uses that do a fantastic job of keeping the oils out of your coffee. This helps to make your coffee extremely clean and fresh, as well. You can also experiment – adjust the coffee-to-water ratio and choose darker coffee roasts.