Preheat a gas grill to medium-high heat. In a small bowl combine all the ingredients except Mahi fillets.
Place filets in a resealable bag and pour marinade mixture over them. Allow to marinade in the refrigerator for at least an hour and up to 4 hours.
Brush Mahi Mahi Fillets with olive oil on both sides.
Grill for 4-5 minutes per side, until golden. Drizzle with lemon juice if desired
Note: to make a quick garlic dill aioli, combine 2 T marinade with 3 T good quality mayo, 1 clove of fresh garlic finely minced and 1/2 teaspoon of fresh or dried dill.