Recipe notes and tips
How do I get the perfect hazelnut crust?
Finely chop the hazelnuts with a knife or pulse briefly in a food processor until coarsely ground, but not powdered. Pat the fish thoroughly dry before brushing it with egg white, then gently press the nuts onto the surface.
Preheat the air fryer and arrange the fillets in a single layer without overcrowding the basket. Good air circulation helps the hazelnuts toast evenly and develop a crispy crust. Avoid turning the fish during cooking to keep the coating intact.
Can I use another fish?
Absolutely! Salmon, Arctic char, or steelhead trout are excellent alternatives. You can also use cod or halibut, although cooking times may vary depending on the thickness of the fillets. Choose fillets that are thick enough to hold together during cooking.
What can I use instead of fennel?
If you’re not a fan of fennel, try thinly sliced green cabbage, cucumber, or zucchini instead. Green cabbage adds a satisfying crunch, cucumber gives the salad a refreshing twist, and raw zucchini has a mild flavor that pairs beautifully with the lemon dressing. Use the same amount and prepare the salad as directed.
Can I make this in the oven?
Yes! Preheat the oven to 400°F (200°C). Arrange the prepared trout on a parchment-lined baking sheet, hazelnut side up. Bake for approximately 12–15 minutes, depending on thickness, until the crust is golden and the fish reaches an internal temperature of 145°F (63°C).
What’s the secret to perfect brown butter?
Use a light-colored saucepan so you can easily see the butter changing color. Swirl the pan frequently and watch closely once the butter starts to foam. As soon as the milk solids turn golden brown and smell nutty, remove the pan from the heat to prevent burning.
Can I prepare the fennel salad ahead?
Yes! You can slice the fennel a few hours ahead and store it in an airtight container in the refrigerator. For the freshest flavor and crunch, toss it with the dressing shortly before serving.
Storage and leftovers
Store leftover trout and fennel salad separately in airtight containers in the refrigerator for up to 2 days. Reheat the fish gently in the oven or air fryer to help preserve the hazelnut crust. The fennel salad is best enjoyed fresh.