Baked Fish With Onions Recipe

Ingredients for Baked Fish With Onions

• Olive Oil
• 2 tablespoons butter
• 2 large yellow onions, thinly sliced
• 2 tablespoons all-purpose flour
• 1 ½ cups whole milk (or plant-based milk)
• Salt And Pepper
• Swiss Cheese
• Cod Fish Fillets
• Fresh Breadcrumb

How to Make Baked Fish With Onions

1. Preheat oven to 400°F (200°C).
2. Melt 2 tablespoons butter with 2 tablespoons olive oil in a large oven-safe skillet or casserole dish over medium heat. Add 2 large yellow onions, thinly sliced, and cook until softened and golden brown, about 15-20 minutes, stirring occasionally.
3. Sprinkle 2 tablespoons all-purpose flour over the onions and cook for 2 minutes, stirring constantly.
4. Gradually whisk in 1 ½ cups whole milk (or plant-based milk for dairy-free version), ensuring no lumps form. Bring to a simmer, then reduce heat and cook for 10-15 minutes, or until the sauce has thickened slightly. Season with salt and pepper to taste.
5. If using cheese, stir in ½ cup grated Gruyere cheese (or your preferred cheese) into the onion sauce.
6. Spread one-third of the onion sauce in the bottom of the prepared casserole dish.
7. Arrange 4 (6-ounce) cod fillets evenly over the sauce.
8. Sprinkle one-third of the remaining cheese (if using) over the cod.
9. Pour the remaining onion sauce over the fish and top with the rest of the cheese (if using).
10. Sprinkle 1/2 cup breadcrumbs evenly over the top. Dot with 1 tablespoon of butter, cut into small pieces.
11. Bake for 20-25 minutes, or until the cod is cooked through and the topping is golden brown and bubbly.