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Fish Pie is a fairly common dish found throughout Britain and Ireland. It consists of a rich and creamy seafood filling topped with a “crust” made from mashed potatoes. Almost always, flour and dairy are used to create a thick roux. But not here! In this version, I riff on the classic by making it dairy-free and gluten-free. It’s still very filling and comforting though.
What You Need for Fish Pie
Fish or Seafood
Fish pie can often be a misleading name for this dish since a wide variety of seafood can be used. Most varieties of flakey, white fish are great in this recipe, such as cod, halibut, or haddock. Salmon and rainbow trout are also a great options! Just make sure to go with boneless and skinless pieces.
You can also use different types of shellfish, including shrimp, scallops, mussels, clams, crab or calamari.
My advice is always to use whatever type of fish or seafood you like or happen to have on hand. It’s a great way to empty out the freezer if you buy frozen filets or packs of shellfish.
In this fish pie, I used a combination of scallops and halibut because both were already in my freezer.
Similar to a Shepherd’s Pie or Cottage Pie, Fish Pie is topped with a “crust” of mashed potatoes. Oftentimes, cheddar cheese and cream is added to the potatoes for flavour, texture and colour. To keep things Whole30, I omitted the dairy here and it still came out beautifully.
The type of potato you use will make a difference. I recommend a white potato, like Russets, which are more starchy and tend to get crispier in the oven. Yellow potatoes, like Yukon Golds, are also great. However, if you use a yellow potato, I STRONGLY RECOMMEND you mash it by hand and do not try to put it in a food processor or blender. If you do, the starches start to break down too much and it will turn into goo.
Rather than use heavy cream or milk for the filling, I opted for full-fat coconut milk. It does tend to impart some coconut-y flavour, but the mustard helps tone it down.
If you are one of those people that absolutely can’t stomach coconut, or happens to be allergic, you can use an unflavoured almond milk creamer, like Nut Pods. I don’t recommend using a regular, store-bought almond milk because it is just too watery and your filling won’t get nearly as creamy.
To thicken the fish pie filling, I make a roux with arrowroot starch. If you’ve never used this alternative flour before, you can think of it like corn starch. It can also be used to dredge proteins like chicken or fish before pan-frying. It is one of my favourite pantry staples and I use it all the time.
Can You Use Chicken to Make Fish Pie
I should have known this question would come up when I originally shared this recipe during my @Whole30Recipes takeover. I get it, fish and seafood is a tough sell for some people.
The answer is: yes, you can substitute pieces of boneless, skinless chicken breast or thigh if you’d like. Of course, you can’t call it fish pie. It would just become a chicken and potato pie, which actually sounds delicious!
Whole30 Fish Pie, Dairy-Free
- 2.5 lbs white or yellow potatoes – roughly chopped
- 4 tablespoons extra-virgin olive oil
- Kosher salt and freshly-cracked black pepper
- 2 celery stalks – diced
- 1 medium carrot – diced
- 2 cloves garlic
- ¼ cup finely chopped fresh parsley – stems and leaves separated
- 1 tablespoon ghee
- 1 tablespoon arrowroot starch
- 16 fl ounces coconut milk
- Freshly-cracked black pepper
- 1 tablespoon Dijon or yellow mustard
- 2 teaspoons hot sauce
- 2 bay leaves
- 1 cup frozen peas
- 6 ounces boneless, skinless fish filets
- 6 ounces shellfish, like scallops or shrimp
- Preheat oven to 375F.
- Bring a large pot of water to a boil, season with 1 tablespoon salt and add the potatoes. Boil until fork-tender, around 15 minutes. Drain and let sit 5 minutes to allow the steam to escape. Add 1 tablespoon olive oil, season with salt and pepper to taste, and mash until chunky. Set aside.
- Heat a saute pan over medium-high heat, add 2 tablespoons olive oil and heat until shimmering. Add the celery, carrot, garlic and parsley stems. Season with a pinch of salt and cook, stirring, until slightly softened, around 8 minutes.
- Add the ghee and stir until melted. Add the arrowroot starch and cook, stirring, until dissolved, 2-3 minutes. Add the coconut milk, mustard, hot sauce, bay leaves, and black pepper to taste. Cook, stirring regularly, until thickened and reduced by half, around 8 minutes. Remove from heat and discard the bay leaves. Stir in the peas and reserved parsley leaves. Taste for seasoning and adjust as desired.
- Scatter the fish and shellfish in the bottom of a medium-sized baking dish. Pour over the cream sauce and top with the reserved mashed potatoes. Drizzle the top with 1 tablespoon olive oil and bake until bubbling and golden brown, 20-25 minutes. Remove from oven and let rest 5 minutes before serving.