Strammer Max is a German open-faced sandwich that's served warm and has numerous variations. It's usually made with a slice of rye or wheat flour bread that can be toasted and buttered or fried in oil or butter. The bread is seasoned with salt, pepper, and (sometimes) mustard.
It is then topped with slices of cured ham and a fried egg to finish it off. Due to the fact that it's quick and easy to prepare the sandwich, it spread throughout the country, but it's especially popular in Berlin, where it's an integral part of the city's food culture.