Heat the butter in a large skillet (the skillet should have straight sides if possible) over medium-high heat.
Cook the chicken until browned on all sides. To get the sides cooked, lay chicken on it's side up against the sides of the skillet.
Add the wine and bouillon.
Reduce heat to low, cover, and simmer for 30 minutes, until chicken is no longer pink and juices run clear.
Transfer the breasts to a warm platter, leaving the juices in the skillet.
Cut & remove string (if you forget this step it is VERY embarrassing)