I first made this on a night when I wanted something “healthy,” but also something that crunched loudly enough to feel like a treat—enter walnut-crusted salmon.
The crispy topping, bright lemon mayo, and buttery fish make it feel fancy, even though it’s basically salmon wearing a very tasty jacket of walnuts and panko.
And the twice-baked colcannon potatoes on the side? Creamy, cheesy, and full of cabbage and scallions—the kind of comfort food that quietly steals the spotlight from the fish.
Crunchy Walnut Salmon with Twice-Baked Colcannon Potatoes
EQUIPMENT (PAID LINKS)
- Zester
- Small whisk
- Aluminum foil
- Small spatula
Ingredients
- 1 lemon zested and juiced
- ½ cup chopped walnuts
- ½ cup panko bread crumbs
- 2 tablespoons garlic herb butter
- 4 salmon fillets
- ⅓ cup mayonnaise
- 4 baked russet potatoes
- 1 ½ cups shredded cabbage
- ½ cup chopped green onions scallions
- ½ teaspoon salt
- ¼ teaspoon black pepper
- 1 cup shredded white cheddar cheese
Instructions
- Prepare Lemon Zest and Juice: Zest the lemon using a zester and set the zest aside. Cut the lemon in half and squeeze the juice into a small bowl.
- Make the Walnut Crunch Topping: In a medium bowl, combine the chopped walnuts and panko bread crumbs. Melt 1½ tablespoons of the garlic herb butter and mix it into the crumb mixture until evenly coated and slightly clumpy.
- Arrange the Salmon: Line a baking sheet with aluminum foil. Place the salmon fillets skin-side down on the prepared baking sheet, leaving a little space between each piece.
- Prepare the Lemon Mayo: In a small bowl, whisk together the mayonnaise, lemon juice, and lemon zest until smooth.
- Coat the Salmon: Spread a thin, even layer of the lemon mayonnaise mixture over the top of each salmon fillet using a spoon or spatula.
- Add the Walnut Crust: Press the walnut and panko mixture onto the mayonnaise-coated tops of the salmon fillets so it forms a thick, even crust.
- Bake the Salmon: Place the baking sheet in a preheated 400°F oven and bake for 10 to 12 minutes, or until the salmon is cooked through and the crust is golden and crisp.
- Prepare the Potato Shells: Slice the baked russet potatoes in half lengthwise. Carefully scoop most of the potato flesh into a large bowl, leaving a thin layer so the skins keep their shape.
- Make the Colcannon Filling: Add the shredded cabbage and chopped green onions to the bowl with the potato flesh. Add the remaining ½ tablespoon garlic herb butter, salt, and black pepper. Mash and mix until the potatoes are creamy and the vegetables are evenly distributed.
- Refill the Potatoes: Spoon the potato mixture back into the potato skins, mounding it slightly so the filling sits above the edges.
- Add Cheese: Sprinkle shredded white cheddar cheese evenly over the tops of the filled potatoes.
- Bake the Potatoes Again: Place the stuffed potatoes on the baking sheet and bake at 400°F for about 15 minutes, until the cheese is melted and lightly golden.
- Serve: Remove the salmon and potatoes from the oven. Let them cool slightly, then serve the crunchy walnut salmon alongside the twice-baked colcannon potatoes.
Video Recipe
Crunchy Walnut Salmon with Twice-Baked Colcannon Potatoes: Tips from Someone Who’s Definitely Made This Too Many Times
A few things I learned after making this dish on busy weeknights, lazy Sundays, and one slightly chaotic dinner party. These are the little tricks that keep it easy and keep you from washing three unnecessary bowls.
Getting the Salmon Actually Crispy
The walnut crust only gets that golden crunch if the salmon isn’t wet, so give it a quick paper towel pat before anything touches it. Moist fish equals sad, soggy topping—ask me how I know. Also don’t press the crust down like you’re compacting soil in a garden; a light press keeps it crunchy instead of dense.
When You Don’t Feel Like Chopping Walnuts
If you’ve ever tried to chop walnuts neatly, you already know they bounce everywhere like tiny kitchen rebels. Toss them in a zip-top bag and smash them with a mug or rolling pin instead. It’s faster, quieter than the food processor, and mildly therapeutic.
Mayo Skeptics, Relax
Yes, the recipe uses mayonnaise, and yes, someone at the table will pretend to be shocked. But once it bakes, it just turns into creamy lemon flavor that keeps the crust stuck to the salmon. Think of it as edible glue, but the delicious kind. If mayo still makes you nervous, plain Greek yogurt works surprisingly well.
Potato Shortcut for Normal Humans
If you’re not in the mood to bake potatoes from scratch, grab microwaveable russet potatoes or leftover baked ones from the fridge. Scoop, mix, refill, done. Cold leftover potatoes are secretly the MVP of this whole recipe.
The Cabbage Situation
Traditional colcannon uses cabbage, but honestly, kale or even bagged coleslaw mix works great here. The potatoes are already doing the heavy lifting flavor-wise. Half the time I use whatever green thing is closest to expiring in my fridge.
Cheese Flexibility (Because Cheese Is Never the Problem)
White cheddar is fantastic, but Monterey Jack, mozzarella, or even a random “Mexican blend” bag will melt beautifully. The goal is gooey, not fancy. If it melts and tastes good, it qualifies as the correct cheese.
Make-Ahead Trick That Saves Your Sanity
You can mix and stuff the potatoes earlier in the day and stash them in the fridge. When dinner time hits, just bake them while the salmon cooks. Future-you will be extremely grateful for past-you’s effort.
Storing and Reheating Without Ruining the Crunch
Leftover salmon keeps well for about two days, but reheating it in the microwave turns the crust into mush. Use a toaster oven or regular oven at 350°F for a few minutes instead. Crispy toppings deserve better than microwave steam.
The Lazy Plating Move
If you’re serving guests and want it to look impressive, sprinkle extra green onions and a little lemon zest on everything. It takes ten seconds and suddenly looks restaurant-y. Garnishes are basically edible makeup for dinner.
