By Chef John

Start with —- 4 fillets
1/4 cup olive oil
1/4 cup lemon juice
1 teaspoon dry mustard
1 clove garlic, finely chopped
1/2 teaspoon salt
1/4 teaspoon pepper
1— place fish in baking dish whisk remaining ingredients until well blended. pour over fish let stand 10 to marinate. preheat grill 375 deg
2 — place fish on grill [discarding marinade] grill 6–7 min on each side serve with salsa.