Creamy keto fish casserole

Creamy keto fish casserole

White fish swimming in a rich and creamy casserole gets kicked up a notch with the briny bite of capers and the freshness of broccoli and greens. A delicious keto dinner doesn’t get any easier than this all-in-one wonder.

Creamy keto fish casserole

White fish swimming in a rich and creamy casserole gets kicked up a notch with the briny bite of capers and the freshness of broccoli and greens. A delicious keto dinner doesn’t get any easier than this all-in-one wonder.
4 servingservings


  • 2 tbsp 2 tbsp olive oil
  • 1 lb 450 g broccoli
  • 6 6 scallionscallions
  • 2 tbsp 2 tbsp small capers
  • 1 oz. 30 g butter, for greasing the casserole dish
  • 1½ lbs 650 g white fish, in serving-sized pieces
  • 1¼ cups 300 ml heavy whipping cream
  • 1 tbsp 1 tbsp Dijon mustard
  • 1 tsp 1 tsp salt
  • ¼ tsp ¼ tsp ground black pepper
  • 1 tbsp 1 tbsp dried parsley
  • 3 oz. 75 g butter
For serving
  • 5 oz. 150 g leafy greens


Instructions are for 4 servings. Please modify as needed.

  1. Preheat the oven to 400°F (200°C).
  2. Divide the broccoli into small florets, including the stem. Peel with a sharp knife or potato peeler if the stem is rough.
  3. Fry broccoli in oil on medium high for 5 minutes, until golden and soft. Season with salt and pepper.
  4. Add scallions, finely chopped, and the capers. Fry for another 1-2 minutes and place the vegetables in a greased baking dish.
  5. Nestle the fish in amongst the vegetables.
  6. Mix parsley, whipping cream and mustard. Pour over the fish and vegetables. Top with slices of butter.
  7. Bake for 20 minutes or until the fish is cooked through, and flakes easily with a fork. Serve as is, or with a luscious green salad.


Mix things up a little bit! Salmon and tuna (fresh or frozen) make awesome substitutes for the white fish. Or, if there’s a broccoli-hater coming to dinner, sub in Brussels sprouts, asparagus, zucchini or mushrooms. Use your imagination and this all-in-one dinner will never get boring.

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  1. Mame
    I made this with cauliflower and cod as someone in the house cannot eat broccoli. It was very good and I will make it again.
  2. Jenn S
    Made this with chicken thighs and spinach and it was really good! I tossed in a little garlic to punch it up a bit, too. Love this recipe, as I've made it with fish too... it's easy to change up now and then!
    Reply: #3
  3. Kim
    Hate fish! If I use chicken breast, how long should it cook?
  4. mel
    Best recipe ever. Made with hoki, broccoli and cauliflower and leek. Will try chicken next time
  5. Rosie Egekwu
    Hi need help with this ketogenie low carb. I don't eat a lot of fried food like pork or beef. I eat chicken and fish . I love yogurt but I haven't had this for three weeks.
    When I started this diet My weight was 210 now I'm 204.2 what I'm doing wrong?
    Please tell me
  6. 1 comment removed
  7. Stephanie
    This recipe is great. I made it exactly as listed with cod and broccoli and it's was very good. The sauce was a little thin, but good flavor.

    Someone suggested making with chicken... it would work with chicken, but you'd probably need to cook it for 30-40 minutes, even if you work it with a meat mallet, which I'd suggest.

  8. Valerie
    Awesome recipe. This is the best fish we've ever made!!
  9. Kim
    Just made this with fresh walleye, Brussel sprouts and spinach and mushrooms. It was FANTASTIC and so easy!! Definitely going to make again, and will make for dinner guests also!
  10. Shirley
    This was amazing. Made it for lunch today. I used Tilapia and cauliflower. I was out of brocolli. My husband hates tilapia and he raved about how good it was. I want to try Kim's (above) recipe. I will definitely make this again with ANY kind of white fish. Y-U-M-M-Y!!!
    Heather I love this dish have made it twice, my Husband loved it too although I did not
    put in the capers. Will try to make it with chicken next time.

    Plus a question has anyone ever hit a plateau I have and do not know what to do to start losing
    weight again.. Will be interested in any reply Thanks Heather V. Aust

  12. Leana Foster
    First of all I found the corn &peas I jusy didnt go down far enough on the page. I do have a question though can you tell me what kinds of fish is considered white fish ? Thanks Leann
  13. Kathleen
    Forgot the mustard and added about 1/4 tsp cayenne - oh my, this is delicious! This is a weight loss plan? 6 weeks in. I wouldn't believe it if the scale wasn't telling me it is.
  14. Katrina
    Genuinely one of the tastiest things I've ever made, keto or not! I put some salmon chunks in there as well as cod lion and it was absolutely banging 😊 am loving eating keto so far 😊
  15. Emily
    Has anyone made this with coconut cream instead of heavy cream? I'm cutting back on dairy due to sensitivity. Thank you!
    Reply: #23
  16. Ravenkeeper
    Very much worthy of five stars. I used Hoki fish and added a bit of baby spinach. My husband said this seafood dish was better than any he had been served in a restaurant.
  17. Val
    Added Parmesan to top it off-best decision. Yum!
  18. Gregory Morris Sr
    When you hit a wall, in your diet, do a 16-18 hour reset (fast) from 9pm to 3pm the next day it will restart the ketogenic process and you should again see weight loss results.
  19. Miranda Edwards
    This is really good and so easy. Add a little lemon juice over the top when serving - delicious.
  20. Aarthi
    I know you've heard this a zillion times, but this is the best keto recipe everrrrrr! LOVED IT! My husband who is not on keto loved it too! Thank you! 👍😀
  21. Jaki
    This recipe is so adaptable.
    I used chopped white onion instead of spring
    Spinach instead of broccoli
    Chopped caperberries instead of capers.
    Sour cream instead of double.
    Didn't have parsley.
    Made with basa fillets.

    Very nice

  22. Kristy
    This is the best white fish dish I've ever had. I can't believe how flavorful it is. I'll make this a thousand times.
  23. Vanessa Feghali
    Just did yes, and its heavenly.
  24. Lynne Favreau
    Made this tonight. My husband doesn't like capers, but didn't notice them until he'd already tasted it and said it was fantastic. Third bite in, "hey, are these capers?" – Ha, too late honey, you love it.
  25. Deborah Clark
    DD: please get an instant pot!
    Reply: #26
  26. Kristin Parker Team Diet Doctor

    DD: please get an instant pot!

    We have a few recipes using an electric pressure cooker! Here's one to get you started.

  27. Katya
    this recipe is so good and it tasted better than what I've had at restaurants!
  28. Jamie Boepple
    This is incredible. It's very decadent, almost impossible to believe this is "diet" food. Restaurant quality. Will make again and again!
  29. Janet
    Made this dish tonight. Gorgeous. I had cod and zuccini (courgette). I doubled the mustard amount because we like mustard and we live in France, not so from Dijon (I have found acceptable mustard). I agree with the comment above, it is really difficult to believe this is "diet" food.
  30. T
    Can I make ahead and cook later?
    Reply: #31
  31. Kristin Parker Team Diet Doctor

    Can I make ahead and cook later?

    Yes, that should work fine.

  32. Victoria
    I also added some mushrooms, 1/2 onion (no scallions), about 2 TBS of fresh lemon thyme, some heirloom cherry tomatoes, and I used fresh parsley rather than dried. Yum!
  33. Beth Loft
    Excellent. We will make this again. I used finely chopped yellow onion as spring onions are so difficult to find in France. I added in 50g of sliced mushrooms that I had in need of using up, used fresh flat leaf parsley because I could, and topped the dish off with a little Parmesan cheese. It was delicious and filling but very rich. Next time I would serve the simplest of green salads on the side to refresh the palate. Being a little bit naughty, I complimented my meal with a small glass of chilled Entre-Deux-Mers - which worked perfectly.
  34. Denney
    I'm going to try this recipe as haddock is on sale at a local market this week, but I'll be leaving out the capers (just don't like capers) and using black olives instead.

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