What type of coffee preparation is featured in a red eye?

In a red eye, the preparation of coffee predominantly features espresso. A red eye is typically made by adding a shot of espresso to a cup of brewed drip coffee. This combination results in a stronger, more caffeinated beverage since the espresso intensifies the flavor and increases the coffee's caffeine content.

Drip coffee serves as the base in this drink, but the key distinguishing factor is the addition of the espresso shot, which is what characterizes a red eye specifically. Understanding the components of a red eye can help in recognizing its unique flavor profile and strength compared to other coffee drinks.