Combine all ingredients, except chicken, in a food processor and pulse until smooth and well combined.

Pour the marinade over the chicken breasts in a wide, shallow bowl (or in a large, sealable plastic bag), and toss to coat. Cover the bowl and refrigerate for at least 2 hours (but no more than 24).

Preheat your gas grill- all burners set to medium. When the grill is hot, add your chicken and cook for 5-6 minutes per side.

Serve with a simple homemade salsa.