1, Wash your hands and cooking area. Preheat oven to 350 °F.
2. Grease an oven- safe dish with as much olive oil as needed. Place grouper fillets on the dish half-an inch apart.
3. Zest, segment, and juice grapefruits; reserve the grapefruit slices.
4. Drizzle grapefruit juice, lemon juice, herbs, and any remaining olive oil over fillets.
5. Bake fish, uncovered, for 30 minutes.
6. Remove the fish from the oven, top with the reserved grapefruit slices, and bake for 5 more minutes.
7. Garnish with additional fresh grapefruit slices if desired.
Nutrition facts per serving: 260 calories, 11g total fat, 1.6g saturated fat, 0g trans fat, 90mg sodium, 5g total carbohydrate, 1g dietary fiber, 0g sugars, 33g protein, 40% vitamin C, and 10% iron. Percent Daily Values are based on a 2,000-calorie diet.