| 1 | Melt 4 tablespoons of butter in a large, heavy skillet over medium heat. |
| 2 | Add the fennel, cover and slowly braise, stirring occasionally, until the fennel is completely softened and lightly browned, about 30 minutes. |
| 3 | Transfer it to a food processor fitted with a steel blade and puree. |
| 4 | Set aside. |
| 5 | Melt the remaining butter in a heavy large saucepan over medium-low heat. |
| 6 | Add the flour and stir with a wooden spoon until the flour is cooked but still light in color, 3-to-4 minutes. |
| 7 | Slowly add the stock to the flour mixture, stirring constantly. |
| 8 | Bring it to a boil, then reduce the heat to low and simmer gently for 30 minutes. |
| 9 | Stir in the fennel, then pass the soup through a fine strainer, if desired. |
| 10 | (the soup may be prepared ahead of time, to this point). |
| 11 | Just before serving, bring the soup to a simmer. |
| 12 | Combine the egg yolks and cream in a small bowl, and beat well. |
| 13 | Gradually add about 2 cups of soup to the yolk mixture. |
| 14 | Slowly blend the yolk mixture back into the remaining soup. |
| 15 | Be careful not to let the soup boil or the eggs will curdle. |
| 16 | Season to taste with salt and pepper. |
| 17 | Ladle into warm bowls and garnish with chives. |
