1/4 c. vegetable oil
1/4 c. fresh lemon juice
1/2 tsp. pepper
6 boneless chicken breasts
3 tbsp. tarragon vinegar
2 tbsp. dry white wine
4 tbsp. butter
2 tbsp. Dijon mustard
1 tsp. tarragon

Marinate chicken in oil, lemon and pepper for 30 minutes. Meanwhile, combine vinegar, wine and tarragon in saucepan and boil until reduced to 2 tablespoons. Reduce heat to low, add butter and mustard, stirring until butter melts; set aside. Drain chicken, grill or broil over medium heat, turning and basting frequently with the mustard sauce (about 5 minutes per side.)