Mince the meat finely either by hand using a knife or a meat grinder. Place it in a bowl.
Separate the egg yolk from the white (reserve the white for another recipe or discard). Add it to the minced beef. You can also retain the egg yolk and add it on top of the tartare as a garnish if you prefer.
Season the meat with salt, pepper and cumin. Follow up with the chopped chives and onion and drizzle everything with olive oil. Mix thoroughly, until everything is well combined.
Shape the mixture into 2 patties and place each one in the center of a serving plate. You can garnish the steak tartare with capers, sundried tomatoes or spicy Tabasco sauce as well if you like.
To serve, toast the rye bread, either in a toaster or in a pan with some butter or olive oil. Add the toasted bread to the serving plates along with a halved garlic clove each. When eating, rub the toast with a garlic and eat with a spoonful of steak tartare.