1 cup chopped sweet onion
1cup lightly packed basil leaves
1/2 cup lightly packed,coarsely chopped italian parsley
3Tbs olive oil
2Tbs sherry vinegar
2Tbs minced garlic
1 1/4 lbs boneless,skinless chicken breasts
1 lb. boneless,skinless chicken thighs
1/2 tsp salt
1/4 tsp pepper
1/3 cup chopped fresh basil
Place onions, basil, parsley, olive oil, sherry vinegar, garlic and 2 TBS of water in a blender and blend until smooth adding additional 1 Tbs water if necessary.
Reserve 1/4c marinade;cover and refrigerate.
Pour remaining marinade in lg. resealable plastic bag. Add chicken,turning to coat. Refrigerate 6-8 hours or overnight,turning occasionally.
Heat grill, remove chicken from marinade;discard marinade.
Sprinkle chicken with salt and pepper.
Grill covered,over med. heat 8-10 min or till no longer pink,turning once.
Sprinkle chicken with chopped basil;serve with reserved marinade.