Steps
1. Preheat your oven to 350F.
2. Line a baking dish with parchment paper and place the fish filet in the center.
3. Mix together the Dijon mustard, olive oil, salt and pepper.
4. Spread the mixture all over the fish, then cover with the basil leaves.
5. Squeeze the juice of half a lemon over the fish.
6. Place the baking dish in the oven and bake for 20-22 minutes, covered with aluminum foil.
7. Uncover the dish and bake for 2 more minutes to get an extra golden color.
8. Serve hot with the remaining lemon.