A block from Plaza de Bolívar is this fine paisa restaurant. It serves lovingly prepared traditional fare, including bandeja paisa and, on weekends, sancocho (soup or stew). The almuerzo ejecutivo (executive lunch; COP$9000) changes every day and is a great deal.
Be sure to try mazamorra, a typical dish made from cooked corn served with a splash of milk and panela (raw sugarcane juice).