Final answer:
Einlauf, a Viennese specialty of strong black coffee topped with whipped cream, is traditionally served with coffee, accompanied by powdered sugar served separately.
Step-by-step explanation:
Always serve Einlauf with coffee (unless coffee is ordered after meal or with dessert). Einlauf is a Viennese specialty, known as a strong black coffee that is often served in a glass and is topped with whipped cream. Accompanying this coffee, powdered sugar is provided separately allowing individuals to sweeten to their taste. There is a specific etiquette to coffee serving in different cultures, and in the Viennese tradition, this sweet and creamy addition beautifully complements the robust flavor of the strong coffee it is paired with.