Creating Roast Snapper with Mandarin and Fennel Sauce is simple if you follow these steps:

1. Preheat the Oven: Begin by preheating your oven to 400°F (200°C). This is the ideal temperature for roasting fish, ensuring it cooks evenly.

2. Prepare the Snapper: Rinse the snapper under cold water and pat it dry with paper towels. Season the inside and outside of the fish generously with salt and pepper.

3. Arrange the Fennel: In a large baking dish or on a sheet pan, lay down the sliced fennel. Add the minced garlic on top of the fennel.

4. Place the Snapper: Gently place the seasoned snapper on top of the fennel layer. Drizzle the olive oil over the fish, ensuring it is well coated.

5. Make the Sauce: In a small bowl, mix together the mandarin juice, honey, and white wine. Pour this mixture over the snapper, allowing it to soak into the fennel and fish.

6. Roast the Fish: Transfer the baking dish to your preheated oven. Roast for about 25-30 minutes, or until the flesh flakes easily with a fork and the internal temperature reaches 145°F (63°C).

7. Garnish: Remove the snapper from the oven and let it rest for a few minutes. Drizzle with the mandarin zest and garnish with fresh dill or parsley before serving.