Chicken with Sherry Vinegar

• 4 tablespoons butter
• 1 chicken (2 to 2 1/2 pounds), quartered, or 4 boneless, skinless half breasts (about 1 1/2 pounds), rinsed and patted dry
• 1/4 teaspoon salt
• 1/8 teaspoon freshly ground pepper
• 1 onion, cut in half
• 1/4 cup sherry vinegar
• 2 shallots, finely chopped
• 3 garlic cloves, finely chopped
• 1 cup dry white wine
• 1 tablespoon tomato paste
• 2 teaspoons Glace de Viande (optional)
• 4 sprigs parsley, chopped

1. In a 12-inch skillet, heat 2 tablespoons of the butter over medium-high heat.
2. Add the chicken and brown well on both sides, about 3 to 4 minutes per side.
3. Season with the salt and pepper.
4. Pour off any excess cooking fat.
5. Add the onion to the pan, cover, and saute gently over low heat for 15 minutes (10 minutes if using breasts).
6. Remove the chicken, but leave the onion, and pour off and reserve any pan juices.
7. Add the vinegar and reduce until almost all of the liquid is evaporated, about 1 minute.
8. Add the shallots, garlic, wine, and reserved pan juices.
9. Return the chicken to the pan, cover, and simmer until the chicken is tender and juices run clear when the chicken is pierced with a roasting fork, about 10 minutes.
10. Remove the chicken and keep it warm on a serving platter.
11. Discard the onion.
12. Stir in the tomato paste and glace de viande.
13. Taste and adjust the seasoning with salt and pepper, if necessary.
14. The sauce should be the consistency of light cream; if it is not, boil to thicken.
15. Remove the pan from the heat and stir in the remaining 2 tablespoons of butter and the parsley.
16. Pour the sauce over the chicken.

butter, chicken, salt, freshly ground pepper, onion, sherry vinegar, shallots, garlic, white wine, tomato paste, parsley

Taken from www.cookstr.com/recipes/chicken-with-sherry-vinegar (may not work)