Step by step recipe:

1. 20 min.
   Peel 300 g potatoes, cut into four, wash and dry.
2. 30 min.
   Pour 2 tablespoons olive oil into a large pan over a low heat, add potatoes, lightly salt and stir well.
   
   Cover and leave to cook, without stiring, on a low heat for at least 30 minutes.
3. 10 min.
   After 30 minutes, uncover and stir potatoes to finish cooking all over (look at this recipe for more information.
   
   Keep hot.
4. 5 min.
   While potatoes are cooking, peel and finely chop 1 shallot.
5. 3 min.
   Cut 2 chicken breasts in two lengthways.
6. 1 min.
   In a frying pan over medium heat, melt 2 tablespoons goose fat, add chopped shallot, salt, pepper and cook one minute.
   
   Add one teaspoon of chopped tarragon.
7. 
   Reduce heat, add chicken breasts, and cook on each side...
8. 10 min.
   ...until they are golden brown.
9. 
   Put them on a hot plate...
10. 5 min.
    ...and cover with aluminium foil, to keep them hot and tender.
11. 10 min.
    Prepare sauce: put frying pan back on the heat, pour in ½ glass dry white wine, ½ glass chicken stock, and a tablespoon chopped tarragon.
    
    Deglaze the frying pan like this until the sauce thickens, then adjust seasoning.
12. 5 min.
    Heat serving plates. In each plate put 2 chicken breasts, coat with sauce, add a sprig of tarragon and surround with sauté potatoes.
    
    Serve immediately.