The Kikopey Nyama Choma ["roasted meat"] Centre sits about 2.5 hours west of Nairobi.
It's a town, truck stop, food court, and club scene, all folded into one. Each restaurant is its own little complex. Facing the street is the butchery; each restaurant has its own.
Immediately next to the butchery is the cooking room.
Here you can see how the rooms are next to each other.
You order by animal and weight and side (i.e. a half kilo of mbuzi [goat] with mataha [that tasteless green potato, corn, bean mash on the left]), all served on a cutting board. The seating area is set back from the street behind the butchery and cooking rooms.
The decor of the restaurant I chose is...appropriate, but discomforting.
I made the mistake of passing through for lunch, between Lake Naivasha and Kericho (via Nakuru), when Kikopey was still recovering from the gluttony of the night before. I ended up having much better nyama choma several days later in Kisumu.