The cubes of meat are first soaked in a marinade - a mixture of oil, salt, chopped onions, garlic and sometimes a chilli. They sit in the marinade for at least an hour so the flavour soaks into every cube. Then the cook threads the cubes onto a wooden skewer, usually four or five per stick.
The skewers are grilled over glowing coals in a small metal box called a charcoal grill. The cook keeps turning them every minute or so to make sure every side is cooked. The smell of grilling brochettes drifts down the street and is one of the most welcoming smells in any Rwandan town.
Brochettes are usually eaten with a side of grilled banana (yes, banana - the cooking kind, called matoke, that goes soft and slightly sweet when grilled). Some places also serve them with chips, chopped fresh tomato and a green chilli sauce called akabanga, which is famously hot - children usually skip the chilli.
Brochettes are a 'shared food'. A group of friends or family will order a pile of skewers, sit around a table, and pull them off the sticks one by one as they chat. It is the kind of meal that takes a long time, with lots of laughter, and nobody is in a hurry to finish.