Preheat the oven to 375 degrees.
To make the gremolata, add the garlic, lemon zest, parsley, parmesan cheese and one tablespoon of olive oil to a small bowl. Mix well and set aside. (May be made one day ahead and refrigerated.)
Rinse the fillets and pat them dry with a paper towel.
To cook the fish, add the remaining tablespoon of olive oil to a large non-stick sauté pan over medium heat. While the pan heats, season both sides of the fillets with salt and pepper.
Add the fillets to the pan and cook for three minutes on each side. Remove the pan from the heat and top each fillet with the gremolata mixture. Place the pan in the oven to finish cooking for 4-5 more minutes. The fish is done when it becomes opaque and flakes easily with a fork. (These cooking times assume that your fillets are one-inch thick. If they are thicker or thinner, they will need more or less cooking time. If they are 1/2 inch or less, they will not need the additional cooking time in the oven.)
Garnish with lemon slices (optional) and serve immediately.
