This easy keto fish pie is comfort food at its best. It has a deliciously creamy filling and a cheesy cauliflower mash topping.
Fish pie is a classic family dinner and one of the first dishes I learned.
The traditional recipe consists of a variety of fish in a white sauce that is topped with mashed potatoes. You then bake it in the oven until the topping is crisp and golden.
It is very simple to turn it into a proper low carb fish pie. I got my inspiration from two different recipes in Vickie De Beer's amazing Low Carb Diabetes Cookbook.
The most important change is to substitute the potato mash with mashed cauliflower. I promise you won't taste the difference. My daughter even declared: "I love the potato mash!"
We make this pie regularly to this day and everyone always comes back for seconds.
This recipe has been on my blog since 2017. I have just updated the post with more details and tips to help you make the recipe perfectly.
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🌟 Why You'll Love This Recipe
- Family-friendly. This fish pie recipe is creamy, tasty and filling. It is the perfect comfort food. If my kids like it, yours will too (my kids are very critical!).
- More vegetables. Here is another win: Your kids eat more vegetables thanks to the cauliflower mash. And the adults benefit from the fact that one portion is keto-friendly with only 8.1g per serve.
- Easy recipe. There are only 20 minutes to prep for this pie. The rest of the time is hands-off. The dish is ready in just one hour. The best thing? Fish pie freezes well, which means it is great for meal prep.
Ingredients
Here are the ingredients you'll need:
For the filling
- White fish fillets. I used hake and cod.
- Onion. Finely chopped.
- Garlic. Fresh is best, but you could replace it with garlic powder.
- White wine. Use a dry wine. Can be substituted with fish stock, vegetable or chicken broth.
- Heavy cream.
- Zucchini. Should be grated. This thickens the sauce.
- Lemon zest, fresh parsley and chives.
For the mash
- Cauliflower. Make sure it is very fresh. If you only have frozen cauliflower or cauliflower rice, squeeze out all liquid after cooking with a cheesecloth or dish towel.
- Butter and Cheddar cheese
- Sour cream or cream cheese
- Chives, Nutmeg and salt
All amounts and details are in the recipe card at the bottom of the post.
Instructions
This is a very simple recipe that even beginners can master easily. Here are the basic steps:
Prep Cauliflower Mash
Step 1: Steam, boil or microwave the cauliflower until soft. Use the tips in my post on keto mashed cauliflower. Drain well.
Step 2: Put the cauliflower florets in a food processor. Add the softened butter, soured cream, cheddar, chives, nutmeg and salt. Blend until smooth. Set aside while you make the filling.
Make The Filling
Step 3: In a large skillet or frying pan, sauté the onions and garlic. Fry until soft and translucent over a low heat.
Step 4: Add the white wine. Cook over a high heat until reduced by half.
Step 5: Add the zucchini, cream, lemon zest and herbs. Season with salt and pepper and let simmer for a while.
Assemble The Pie
Step 6: Put the fish fillets in a casserole dish and pour over the sauce. Spread the cauliflower mash on top.
Bake In The Oven
Step 7: Bake the fish pie in the preheated oven for 40 minutes or until the mashed cauliflower topping is golden brown.
Serve with a crisp green salad, a side of green beans or enjoy all on its own.
Expert Tip
It is essential that the cauliflower is very soft, but not watery. If you have steamed it, pat it dry. If you have boiled it, drain the water and then put it back in the pot. Let any residual moisture cook off, without letting it burn.
Variations
I have made this keto fish pie countless times over the years, and I love tweaking ingredients. Here are some variations we have tried and tested:
#1 Don't like cheese? Make the cauliflower mash from my keto cottage pie recipe.
#2 Any white fish works, as well as salmon or prawns or even lobster. You can also try a smoked fish.
#3 Celery and green beans work well in addition to the zucchini.
Recipe FAQs
Of course. Simply fill into single serve ramekins.
For a dairy-free version, use a dairy-free cream instead of the heavy cream. Use olive oil instead of the butter in the cauliflower mash and add either a vegan cheese or nutritional yeast for a cheesy taste.
Single cream (or half and half) is more watery than heavy cream or double cream. I don't recommend it.
Storage
Refrigerator: Store keto fish pie in the fridge for up to 3 days.
Freezer: Freeze for up to 3 months. Thaw overnight in the fridge, the reheat in the oven or in the microwave.
If you love fish recipes as much as I do, also check out my Low Carb Keto Fish Tacos!
More Easy Keto Dinners
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Recipe
Low Carb Keto Fish Pie
from Sugar Free LondonerNote: The servings slider only changes the first amount in each line and not any subsequent amounts. Please make your own calculations where necessary.
Ingredients
For the filling
- 1 onion chopped
- 2 garlic cloves chopped
- 1 cup dry white wine (250ml)
- 1 cup double/heavy cream (250ml)
- 3 medium zucchini 550g, grated
- grated lemon zest from 1 unwaxed lemon
- handful of fresh parsley and chives chopped
- 1.75 lb hake and/or cod fillets (800g) without skins
- pepper and salt to taste
For the cauliflower mash
- 1 very large or 2 smaller cauliflower heads 700g
- 3 tablespoon melted butter 40g
- ½ cup soured cream or cream cheese, (125g)
- 1 cup cheddar shredded (125g)
- 1 tablespoon chopped chives
- ¼ teaspoon nutmeg
- salt to taste
Instructions
Cauliflower Mash
- Separate the cauliflower into florets and steam/ boil/ microwave until soft. Follow the tips in my keto mashed cauliflower recipe.
- Add the butter, soured cream, cheddar, chives, nutmeg and salt. Blend in a food processor or with an immersion blender until smooth.
- Preheat oven to 200 Celsius/400 Fahrenheit (electric) or 180C / 360 F fan.
Fish filling
- Fry the onions and garlic in olive oil over a low / medium until soft and translucent, around 3 minutes. Do to burn.
- Add the white wine. Turn up the heat to high and reduce by half.
- Add the grated courgettes, cream, lemon zest and herbs and simmer for 5 minutes. Season with salt and pepper.
Assembly
- Put the fish fillets in a casserole dish and pour over the sauce.
- Spread the cauliflower mash on top and run a fork over the top to make lines.
- Bake in the oven for 40 minutes or until the top is browned.
- Sprinkle with some fresh parsley and serve.
Alex
Hi, just trying to work out the nutrition values. What would you roughly say the grams are per portion that you’ve supplied? I know you’ve put that there are 6 portions.. but what was the original weight so I can add in my side?
I’ve tried and was so lovely by the way,
I also was a little naughty and added crispy bacon bits, and also tried an alternative method with mashed butternut squash one time as I didn’t have cauliflower and was also yummy.
Mirth
this is absolutely delicious. Neither of my teen sons are fans of white fish normally - find it a bit dry and not filling enough. My youngest pulled a face when I said we were having fish for dinner but...absolutely lapped it up and had the leftovers for breakfast! Nb I had only one smaller cauliflower and added some (also low carb) turnips to the mash - made for the best tasting and textured low carb mash ever (1 cauli, three small turnips). I'll definitely be making this again.
Sammie mckee
I was just wondering it seems you don't coo the fish first would it work if you added the fish to the stock/wine or in the last 5 mins with the other filling ingredients? Or would this make it mushy or change the flavour too much?
I've never cooked fish let alone a fish pie but this sound super yummy I'm hoping you can convert me
Katrin Nürnberger
You can probably add the fish in with the other ingredients for the last 5 minutes it you prefer that, I don't think it will make much of a difference. It will cook through in the oven though!
Claire
Can’t wait to try this, sounds delicious. How do you reheat the leftovers? Or is it better to eat them cold?
Katrin Nürnberger
I just stick it in the microwave! Or re-heat in the oven, just like you would a regular fish pie 🙂
Hannah Lloyd
Cant wait to try this recipe ive been needing this in my life since doing keto ha!
is sour cream better than cream cheese? or what did you use?
Katrin Nürnberger
I used sour cream, but both will work.
Sanna
I made this for the second time, this time with broccoli instead of cauliflower. Both times, it was absolutely delicious and so comforting today, on this colder Spring day.
Katrin Nürnberger
It was freezing here today too!! Glad it hit the spot 🙂
JK
I don’t want alcohol in my home, what can I use as a substitute for the wine?
Katrin Nürnberger
I would just use vegetable or fish stock instead.
Wendy Lander
I don't have alcohol in my house either. I will use de-alcoholised wine when I make this. I did that when I needed wine for a special spaghetti Bolognese which turned out really well.
DonnaL
I have some cod in the freezer and didn't know what to do with it. Now I know what I'm going to do with it.
Can you tell me what size casserole dish you used?
I live in Arizona... USA... Thanks for the recipes you have converted to low carb.
Katrin
Hello there, I used a 13 x 9 inch casserole dish. Hope you'll try the recipe!
Becky
Hiya katrin
I found your site at Xmas and decided I was going to supplement your low carb recipes as an evening meal with my milkshake diet, after a week of trying your very tasty recipes I got rid of the milkshakes and went with just your recipes, I’ve lost 14kg since Boxing Day, I’m a definite convert, your recipes are tasty, easy to do and very filling!!!!!! Your fish pie is most definitely my favourite however (the point of this message) can I use single cream instead of heavy cream?
Cheers
Katrin
You must be so happy - 14 kilos, amazing! I think you can use single cream, but as it's more liquid you may want to use a little less / reduce the sauce a bit more to make up for this.
Julie B.
Hello Katrin, I am new to your site. I was looking up desserts and found this one later. You got me at comforting and fish. We liked it but I think that the fact that my fish was frozen, it was watery. I think my second version will be better. I am writing to you from Quebec, Canada. Cheers to your day. Julie
Katrin
Hi Julie, I'm sure you can use the same fish again, just make sure you reduce the liquid more before putting it in the oven!
Julie
Hi again, I forgot to mention that I have a keto lifemeal now. I would love more one pan meals. Bye for now!
Katrin
Noted! 🙂