My mother never wrote this recipe down. She just stood at the stove, humming, layering sweet onions under halibut and spooning cream over the top. I watched her make it countless times, and now it has become one of my favorites to share. It is simple, comforting, and always brings people back for more.
Halibut Olympia
Posted by : Tyler Martinez / On : Oct 02, 2026
Halibut Olympia
Rated 5.0 stars by 1 users
Cuisine
American / Pacific Northwest
Servings
2
Prep Time
15 minutes
Cook Time
25 minutes
Calories
1058
A nostalgic midcentury casserole that's as comforting as it is elegant. This recipe features tender halibut fillets baked over a bed of sweet, caramelized onions and smothered in a rich, tangy cream topping.
Ingredients
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2 halibut fillets (6–8 oz each, about 1-inch thick)
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Salt and black pepper, to taste
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1 large yellow onion, thinly sliced
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1 tablespoon butter
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½ cup mayonnaise
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¼ cup sour cream
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1 tablespoon fresh lemon juice
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1 teaspoon Dijon mustard
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1 clove garlic, minced
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¼ teaspoon paprika
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Salt and black pepper, to taste
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½ cup panko breadcrumbs
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¼ cup grated Parmesan cheese
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1 tablespoon butter, melted
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1 tablespoon fresh parsley, chopped (plus extra for garnish)
Directions
Preheat your oven to 400°F. In a skillet over medium heat, melt the 1 tablespoon of butter. Add the sliced onions and cook, stirring occasionally, until they are soft, golden, and caramelized, about 10–15 minutes. Spread the caramelized onions evenly in the bottom of a small baking dish.
Pat the halibut fillets completely dry with a paper towel. Season both sides generously with salt and pepper. Place the fillets on top of the caramelized onions in a single layer.
In a small bowl, combine the mayonnaise, sour cream, lemon juice, Dijon mustard, minced garlic, and paprika. Season with a pinch of salt and pepper. Mix until smooth. Spread this mixture evenly over the top of the halibut fillets.
In another small bowl, combine the panko breadcrumbs, Parmesan cheese, melted butter, and chopped parsley. Mix until the crumbs are evenly coated. Sprinkle the crumb mixture generously over the cream topping.
Place the baking dish in the preheated oven and bake uncovered for 20–25 minutes, or until the topping is golden brown and the fish flakes easily with a fork. The internal temperature of the fish should reach 130°F–135°F for medium.
Remove from the oven and let rest for 5 minutes before serving. Garnish with additional fresh parsley and serve with lemon wedges on the side.
Recipe Note
SIMPLE SIDE SUGGESTIONS (optional)
Light meal: Serve with a simple green salad dressed with a light vinaigrette to cut through the richness.
Hearty meal: Pair with rice pilaf or roasted asparagus and crusty bread to soak up any extra sauce.
CHEF'S SUBSTITUTION GUIDE
If you prefer a milder white fish: Substitute Cod, Haddock, or Pollock – they offer a similar neutral flavor and flaky texture.
If you prefer something richer: Substitute Sablefish or Chilean Sea Bass – they provide a more buttery profile.
If you don't have panko: Substitute crushed Ritz crackers for a classic, buttery crunch.
Nutrition
Calories 1058, Carbs 22 grams (7%), Protein 84 grams (168%), Fat 69 grams (106%), Saturated Fat 20 grams (125%), Trans Fat 1 grams, Cholesterol 281 milligrams (94%), Fiber 2 grams (9%), Sugar 6 grams, Sodium 1480 milligrams (64%), Iron 2 milligrams (11%), Potassium 2022 milligrams (58%)
