Keto tuna casserole

Keto tuna casserole

Just like mom used to make—but with a keto upgrade! Ditch the noodles in favor of celery, onions, and peppers, and indulge in a keto meal that's ready in 30 minutes. It's a whole new, delicious thing.
October 2 2017 recipe by , photo by , nutritional review by in Recipes, Dinner, Meal

Keto tuna casserole

Just like mom used to make—but with a keto upgrade! Ditch the noodles in favor of celery, onions, and peppers, and indulge in a keto meal that's ready in 30 minutes. It's a whole new, delicious thing.
USMetric
4 servingservings

Ingredients

  • 1 oz. 28 g butter
  • 1 (4 oz.) 1 (110 g) yellow onion, finely choppedyellow onions, finely chopped
  • 1 (5 oz.) 1 (140 g) green bell pepper, finely choppedgreen bell peppers, finely chopped
  • 5½ oz. (1½ cups) 160 g (375 ml) celery stalk, finely choppedcelery stalks, finely chopped
  • 1 lb 450 g tuna in water, drained
  • ¾ cup 180 ml mayonnaise
  • 1 cup (2¾ oz.) 240 ml (80 g) shredded Parmesan cheese
  • 1 tsp 1 tsp chili flakes
  • salt and pepper
Serving
  • 6 oz. (52⁄3 cups) 170 g (1.3 liters) baby spinach
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Instructions

  1. Preheat the oven to 400°F (200°C). Fry onion, bell pepper and celery in butter in a large frying pan until slightly soft. Season with salt and pepper.
  2. Mix tuna, mayonnaise, parmesan cheese, and chili flakes in a greased baking dish. Add fried vegetables and stir.
  3. Bake for 15-20 minutes or until golden brown.
  4. Serve with baby spinach.

Tip!

Canned tuna is a life-saver when fridge and freezer are empty. Try to choose high-quality, MSC-labeled tunafish—preferably in olive oil instead of sunflower oil.

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1 2

79 comments

  1. 1
    Chad
    September 25 2017
    Very filling and the tuna was a welcome change from all the yard-bird I've been eating lately. This was very quick and supper simple to fix. I did omit the green bell pepper and chili flakes I love them both but not sure I would use them with tuna. I did sprinkle the top with bacon bits and a thin layer of a fiesta cheese mix before putting it in the oven. I might add some green peas, mushrooms and pimentos next time although will bump up the carbs a bit.
  2. 2
    suzann
    October 3 2017
    Do you foodies think i could sub salmon? I'm new to sea food but I've got some salmon in the freezer.
  3. 3
    Carole
    October 5 2017
    This is pretty good, not exciting, but I'll make it again. I followed the recipe pretty closely. The parmesan gets some crunchy bits in the oven, which is great. I used tinned tuna, but you could also use tinned salmon.
  4. 4
    Maha
    October 5 2017
    I made this last night, and holy tuna casserole, was this delicious! I followed the recipe nearly exactly (yellow bell pepper instead of green, less chili flakes to taste). My kids loved it too, even my pickier eater. My other son wanted to make sure there were leftovers for his lunch today. And I'm looking forward to lunch too! This is a great recipe to double or triple and freeze in portions. I think the key to this recipe is to use quality ingredients. The mayonnaise I bought is a small fortune, but it's made with normal ingredients (except the soybean oil) and tastes really good. The tuna I use is not the yucky standard that is cooked twice, but one that is cooked just once and retains all the yumminess of tuna. I think this recipe lends itself well to variations - adding mushrooms, using jalapenos, making lettuce boats/bites, topping a tomato bowl or slice and add chopped avocado, etc. An excellent recipe, thank you!
  5. 5
    Cindy
    October 7 2017
    Very good! I used chopped up broccoli stems since I didn't have a pepper on hand. Also added mushrooms and cheddar cheese on top. I'll be making this again!
  6. 6
    carol
    October 10 2017
    Just made this, with grated mozzarella and grated cheddar on top. Lovely.
  7. 7
    Unni Furseth
    October 20 2017
    One of my favorites! I'm just about to make 12 portions and freeze, so I have something delicious the days I don't have the time to cook. And you get first class mayonnaise by making it yourself, recipe on this fantastic website! Thank you for all these wonderful, tasty keto recipes!!!
  8. 8
    Ibán
    November 1 2017
    very tasty thanks!
    however mine came out with a lot of oil on the bottom of the pan, maybe because I used olive oil based mayonnaise
  9. 9
    Rads
    November 20 2017
    Hi! This looks delicious. I live in India and ovens are not staple here, just stove tops hobs. Can I make this on stove top? If yes, how long should the mix cook? Or is it better to make this in an electronic slow cooker, which I have?
  10. 10
    Rads
    November 20 2017
    And can I use fresh tuna chunks, which I just froze today!
  11. 11
    Karina
    November 27 2017
    Loved it!
  12. 12
    Brenda
    December 20 2017
    Does this really take 4 4oz cans of tuna to make the 1 pound?
    Reply: #14
  13. 13
    Phil
    February 12 2018
    Perhaps my mayo in the UK is different but the amount of oil when I took it out of the dish was incredible and swamped the plate ... I followed the recipe exactly? Any ideas? or maybe I can replace the mayo with something else?
  14. 14
    Reply to comment #12 by Brenda
    Hlhabq
    March 13 2018
    I had the same question when u saw the amount of things cheese in the recipe.
    Reply: #15
  15. 15
    Reply to comment #14 by Hlhabq
    Hildyhorse
    March 14 2018
    ... amount of TUNA...
  16. 1 comment removed
  17. 17
    Jared
    March 16 2018
    To be honest: I was surprised this was good as it was. Made no substitutions, followed directions exactly and it was a win. If you ever had a subway tuna sandwich that was toasted to be warm, it's just like that.
  18. 18
    Carrie
    March 22 2018
    I had major reservations about this recipe mainly due to the all mayo base, but this turned out great! I used a 7 oz can of tuna in water instead of oil. And also added shredded cheese on top. I think I could double the tuna next time and sub some different veggies...definitely satisfied my comfort food craving while trying to stick to low carb!
  19. 1 comment removed
  20. 20
    Matt
    May 11 2018
    Are these nutrition facts per serving? Thanks
    Reply: #21
  21. 21
    Reply to comment #20 by Matt
    Peter Biörck Team Diet Doctor
    May 11 2018
    Hi Matt!

    Yes. :)

    Are these nutrition facts per serving? Thanks

  22. 22
    Nicoleta
    May 19 2018
    It was the first time I tried baking mayo and I have to say I'm not a huge fan of the process. The recipe sounds great but, as you'd expect, most of the oil separates from the egg yolk during baking and you're left with and incredibly oily warm tuna salad with sauteed vegetables. Still, it was a good attempt at innovation.
    Reply: #48
  23. 23
    Christy
    June 6 2018
    The mayo in this recipe was really disgusting to me -- oil everywhere. I'm going to search for another recipe for tuna casserole or figure out some way to modify this. Sour cream, maybe?
    Replies: #39, #49
  24. 24
    Jill
    July 24 2018
    I made this last night to keep for dinner throughout the week. I am pleasantly surprised at how good this turned out. Like someone else, I also used canned tuna in water and drained it. I used 3 cans and kind of eye balled the rest of ingredients. I also added two cloves of garlic and topped mine with shredded mozzarella because I’m a cheese addict. Came out so good. It’s definitly a refreshing recipe from all the red meat and chicken I’ve been eating. I lost 20lbs following recipes and advice from this site, such a great resource!
  25. 25
    Gloria
    July 25 2018
    i wasnt sure how this would turn out, but it was the quickest, easiest, most delicious meal i've made. everything complimented everything perfectly ! love it, defs one of my faves 😊😊
  26. 26
    Rosemary
    July 30 2018
    Did not this at all. I agree with Christy. Oil everywhere. Too greasy. Hardly any taste to it.
  27. 27
    Michelle
    August 30 2018
    Could you use sour cream instead of mayonnaise?
  28. 28
    Cindy
    September 25 2018
    can someone help me please! I'm confused I put for one person and when I open the recipe it says four servings. Does that mean I can have up to four servings? lol sorry if it sound silly.
    Reply: #30
  29. 29
    Jacqueline
    September 27 2018
    This is the most delicious thing I have eaten in my entire life!
  30. 30
    Reply to comment #28 by Cindy
    Jacqueline
    September 27 2018
    You can alter the recipe for one serving and it gives you the calorie, carb, fat breakdown down below
  31. 31
    Nicole
    October 11 2018
    Absolutely delicious! I topped with mozzarella cheese and love the chilli flakes.
  32. 32
    Brenda
    October 16 2018
    Hi all , tuna makes me repeat can I use the canned chicken instead ? Thank
    Brenda PM ( since the is more than 1 Brenda 😀
  33. 33
    Margot Campos
    October 18 2018
    I really wanted to like this dish but found myself disappointed. It was way too oily and I didn’t like the taste.
  34. 34
    Katheryn
    November 2 2018
    I agree with Margot. It was too salty and heavy and I didn't like it all. Fortunately, my husband loved it so he can finish it off.
  35. 35
    Dorothy
    November 19 2018
    Yum! Very, very tasty indeed. I only had supermarket mayo to hand and substituted mushroom for pepper. Will definitely make again, thank you!
  36. 36
    Jacolyn
    December 7 2018
    I made this tonight for dinner and I liked it! Loved the hint of the hot peppers. I actually added spinach to it instead of on the side. I will make this gain. Very filing too!
  37. 37
    Lucy
    December 11 2018
    Can I use canned tuna in water or does it have to be in olive oil? Also can I sub out parm cheese for regular cheese?
    Reply: #38
  38. 38
    Reply to comment #37 by Lucy
    Kristin Parker Team Diet Doctor
    December 12 2018

    Can I use canned tuna in water or does it have to be in olive oil? Also can I sub out parm cheese for regular cheese?

    You can use either tuna you prefer. For the cheese, if you make a sub, it can affect texture and taste as other cheeses don't behave the same in baking as parmesan. You can experiment to see if it works for you though.

  39. 39
    Reply to comment #23 by Christy
    Julia Britt
    January 22 2019
    Agreed. I added a bit of turmeric and cayenne because it didn't look appetizing to me. It is waaaay too rich. It needs noodles to make it worth eating more than one bite, but then its not or to friendly. Never again!
  40. 40
    Sherri S.
    January 27 2019
    I purchase the BIG cans of water-packed tuna at Sam's Club or Gordon Foods as you get a LOT more tuna and less juice than when you try to use the smaller cans, perfect for preparing family-sized meals and you aren't opening 8-12 smaller cans of mostly juice. The price is reasonable, too, when buying tuna like that. You get large chunks of tuna as opposed to fine shreds. I keep a few small cans around if I want to prepare a small amount for my lunches, but always have a large can for casseroles in the pantry.
  41. 41
    Emma
    February 5 2019
    I'll be honest I didn't hold out much hope for this recipe; it just seemed too simple. However it was incredibly tasty, looking forward to my dinner tomorrow now!!!
  42. 42
    Erica
    February 10 2019
    I made this recipe last night. It was very oily and creamy. I used my keto Mayo and felt it may have been better with sour cream. However, it had a delicious taste. I might try the recipe again with a few modifications.
  43. 43
    Johnda
    February 12 2019
    1 pound is equal to 16 ounces. 4x4 is 16.
  44. 44
    Elisabeth
    February 24 2019
    This was very tasty and will quickly be one of my favourites. Thanks to everyone who contributes to the recipes...makes life so much easier
  45. 45
    Mieka
    March 7 2019
    I've never eaten tuna casserole in my entire life. Looks like I'm about to try it. :-)
  46. 46
    Dianna
    March 15 2019
    Very tasty! I used Avocado mayonnaise and it wasn’t too greasy but I did top with a mixture of cheddar and jack cheese
  47. 1 comment removed
  48. 48
    Reply to comment #22 by Nicoleta
    The Ghost Critic
    March 26 2019
    Oil doesn’t separate if you did it right
  49. 49
    Reply to comment #23 by Christy
    The Ghost Critic
    March 26 2019
    No sour cream, just follow directions 😈
  50. 50
    Paulina
    April 17 2019
    Can I freeze
    Reply: #51
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