Remove the zest of the orange with a microplane or zester and separate the orange segments.
Prepare the oil
Combine the oil and the zest and simmer for 5 minutes.
Let the orange zest infuse while the oil is cooling.
Make the dressing
Cut the outer leaves of the fennel into small pieces.
Add 1 tbsp of grapeseed oil, 1 tbsp of water, pastis, and fennel seeds. Cook in a covered pan over a low heat until soft and tender.
Blend to a purée and combine with the cheese, vinegar and 2 tbsp of grapeseed oil until a smooth texture.
Pass the mixture through a thin mesh sieve. Season to taste and set aside.
For the salad
Use a mandolin to slice the heart of the fennel bulbs into transparent slices.
Place the fennel into iced water for 20 minutes.
Drain and pat dry the sliced fennel before tossing together with the orange segments, a pinch of salt and pepper, the infused oil, and a lot of chopped dill.
Pan fry or grill the fish fillets.
Notes
Plunging the fennel in iced water will make the vegetable crisp.
Make the orange oil in advance. It keeps in the fridge for up to a month.
If you need some zest and you can’t find organic oranges, blanch them for 1 minute to remove pesticides, chemicals or wax that may be on them.