Walnut-Crusted Trout with Green Beans Recipe

What Is Walnut-Crusted Trout with Green Beans?

Walnut-Crusted Trout with Green Beans takes the classic technique of pressing chopped nuts onto fish before roasting and swaps the usual almonds for walnuts, skipping the bread crumbs entirely. Rainbow trout fillets get a layer of Dijon mustard topped with finely chopped walnuts, lemon zest, garlic and parsley, then roast on the same sheet pan as the green beans until the crust turns deep golden and the fish flakes easily.

What Makes This Recipe Anti-Inflammatory?

Rainbow trout is an oily fish that supplies EPA and DHA, the long-chain omega-3 fatty acids the body converts into resolvins and protectins, the compounds that help bring an inflammatory response to a close. Walnuts are the nut richest in alpha-linolenic acid, the plant form of omega-3, and they also carry polyphenols called ellagitannins.

The extra-virgin olive oil drizzled over the crust and tossed with the beans supplies oleocanthal, a phenolic compound that reduces the activity of the COX enzymes involved in the inflammatory response. The walnut crust replaces bread crumbs, so the dish contains no refined flour, no added sugar and no refined seed oils, while the green beans add fiber, vitamin K and carotenoids.

Ingredients

• 4 rainbow trout fillets (about 5 ounces each), skin on
• 3/4 cup raw walnuts, finely chopped
• 2 tablespoons Dijon mustard
• 1 lemon, zested and then cut into wedges
• 3 tablespoons extra-virgin olive oil, divided
• 2 cloves garlic, minced
• 1/4 cup fresh flat-leaf parsley, chopped
• 1/2 teaspoon dried thyme
• 1 pound green beans, trimmed
• 3/4 teaspoon fine sea salt, divided

Directions

Step 1

Preheat the oven to 425 degrees Fahrenheit and line a large sheet pan with parchment paper.

Step 2

Toss the green beans on the pan with 1 tablespoon of the olive oil, the dried thyme and 1/4 teaspoon of the salt, spread them in a single layer and roast about 8 minutes, until they turn bright green and start to blister in spots.

Step 3

Stir the chopped walnuts, the lemon zest, the minced garlic, the chopped parsley, 1 tablespoon of the olive oil and 1/4 teaspoon of the salt together in a small bowl while the beans roast, until the walnuts look evenly moistened.

Step 4

Pat the trout fillets dry, season them with the remaining 1/4 teaspoon salt and brush the flesh side with the Dijon mustard.

Step 5

Press the walnut mixture onto the mustard with the back of a spoon so it holds in an even layer.

Step 6

Push the beans to the edges of the pan, lay the fillets skin side down in the center and drizzle the remaining 1 tablespoon olive oil over the crust.

Step 7

Roast about 12 minutes, until the crust is deep golden and the fish flakes when pressed with a fork at the thickest point.

Step 8

Squeeze two of the lemon wedges over the fish and the beans, and serve the rest of the wedges on the side.

Nutrition Facts (per serving)

InflammaScore

1 Good! Very low inflammation potential

Q&A

Q1: Can I use a different fish instead of trout?
A1: Yes. Any fillet of similar thickness works, such as salmon or arctic char. Pat it very dry before brushing on the mustard, since a damp surface keeps the walnut crust from sticking and the fish steams instead of developing a golden top.

Q2: How should leftovers be stored?
A2: Store the fish and the beans in a sealed container in the refrigerator for up to two days. Reheat them gently in a 350 degree Fahrenheit oven for about ten minutes, since a microwave turns the walnut crust soft instead of leaving it crisp.

Q3: Why did my walnut crust fall off instead of staying in place?
A3: The crust needs a dry surface and firm pressing. Pat the fillets completely dry before the mustard goes on, then press the walnut mixture down with the back of a spoon so it bonds to the mustard instead of sitting loosely on top.

Q4: Can the walnut topping be made ahead of time?
A4: Yes. Mix the walnuts, lemon zest, garlic, parsley, olive oil and salt up to a day ahead and keep the bowl covered in the refrigerator. Bring it to room temperature before pressing it onto the mustard so it spreads evenly.

Q5: Who is this dinner a good fit for?
A5: Anyone who wants oily fish, a green vegetable and a crust with no refined flour in about half an hour on a single pan. It does not suit anyone with a tree nut allergy, since the topping is built entirely from walnuts and no substitute gives the same texture.

The whole dinner roasts on one sheet pan in 35 minutes, with the beans going in first and the fish joining them halfway through. The walnut topping can be mixed and pressed on ahead, so the pan slides into the oven right before serving.