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A breadcrumb-free, gluten-free, keto cod au gratin
Cod is a common fish favorite for its exceptionally mild flavor, meaty texture, and beautiful white color. And if you are a non-fishy fish lover, like myself, who enjoys rich and crispy fried fish but prefers a more light and healthy baked fish without all that breading, this recipe is for you!
Oh, and one more thing. This keto cod recipe is breadcrumb-free, making it gluten-free, low-carb, and high-protein. BOOM!
The richness in this recipe comes from the gratin—a fancy French word for “a light browned crust of breadcrumbs or melted cheese.” This time, we skipped the breadcrumbs and opted for fatty nuts, Parmesano Reggiano, and extra-virgin olive oil. The nuts provide a crunchy texture and the cheese and oil bind everything together. Fragrant herbs and aromatic garlic add freshness while baking the fish keeps it light and healthy.
What you will need to make keto cod au gratin: Just 10 ingredients
Perhaps, what I like most about this recipe is that it doesn’t take much time or resources to create a quick, easy, and super healthy main dish. That’s why I make it, like…ALOT! Especially, since being on my postpartum weight loss journey. Easy peasy, and super tasty!
Here’s the lineup:
Ingredients
- 4 six-ounce pieces of cod, fresh or thawed
- A large garlic clove
- Shelled walnuts
- Gourmet Garden Lightly Dried Chives* or fresh chives, chopped (see Notes on the recipe card)
- Gourmet Garden Lightly Dried Basil* or fresh basil, chopped (see Notes on the recipe card) (Read more about why I live these lightly dried herbs)
- Grated parmesan cheese
- Fresh thyme sprigs (about 5-6 of them)
- Extra virgin olive oil (or garlic-infused olive oil)
- Sea salt (or as needed)
- Ground black pepper
Tools
- A small food processor (or a mezzaluna–read more about how I used this in my Green Olive Salsa Verde recipe)
- Measuring cups and spoons (these are my favorite gold ones!)
- Glass baking dish (2 Qt. square for 2 pieces of fish -OR- 3 Qt. oblong for 3 pieces of fish)
How to make quick and easy keto cod au gratin: Step-by-step
1. Make the breadcrumb-free gratin
It’s time to put your small food processor to work! Start by blitzing the garlic until well-minced.
1. Mince the garlic. 
2. Add nuts and herbs; pulse. 
3. Add in the cheese; pulse. 
4. Stir in oil and seasonings.
Next, add the nuts and herbs and pulse until it becomes a coarse, crumb-like texture. Be careful not to over-process the mixture at this point. We don’t want walnut-herb butter, here…but an elegant gratin (with a beautiful French accent applied).
Now, it is time for the best part. CHEESE. Make sure to pulse until just combined, making the gratin mix a slightly finer crumb.
Dump it into a small bowl, drizzle in the oil, and give it a sprinkle of salt, and a dash of pepper. Mix well and get ready to gratin your fish.
2. Prep the cod and top it with the gratin
Begin by patting the fish dry with a paper towel (to avoid over-streaming while baking). Place the fish pieces into a baking dish, then lightly season with olive oil, salt, and pepper.
Here comes the fun part! Top each piece of cod with a couple of spoonfuls of that glorious gratin mixture. Don’t be shy to pile it on generously (saving enough for each piece, of course…unless your feeling stingy).
1. Pat the cod dry & season it. 
2. Top the cod with gratin.
What to do with any leftover gratin mix
When making this for two people, I just add extra gratin on top of each piece of cod, then save any extra for another dish. It’s a great topper for other types of baked fish or chicken, salads, and even eggs! Baking the gratin is not required for it to still be delicious.
You can store it in the fridge for up to 2 weeks.
3. Bake until golden and serve with a smile
It’s almost time to impress your tastebuds! Place the gratin-ed fish in the oven and bake it at 375 degrees F for 9-15 minutes, depending on the thickness of the pieces. You’ll know it’s ready when the internal temperature reaches 145 degrees F and the gratin is golden brown.
Yay! It’s ready. Enjoy, friend.
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Try these other light, healthy, gluten-free fish recipes
Watch how to make this Keto Cod au Gratin
Walnut & Herb Cod au Gratin (Keto/Gluten-free)
If you like rich and crispy fried fish but prefer a more light and healthy baked fish without all of the breading, you can guiltlessly indulge in this baked cod recipe. The gratin is breadcrumb-free! Made with only walnuts, herbs, and cheese, it's gluten-free, low-carb, high-protein, and keto. Boom!
Ingredients
Gratin
- 1 large garlic clove
- 1/2 c shelled walnuts
- 2 TB Gourmet Garden Lightly Dried Chives* or fresh chives, chopped (see Notes)
- 2 TB Gourmet Garden Lightly Dried Basil* or fresh basil, chopped (see Notes)
- 3 TB grated parmesan cheese
- 5-6 sprigs of fresh thyme (about 1 TB)
- 1 TB extra virgin olive oil (or garlic-infused olive oil)
- 1/4 tsp sea salt (or as needed)
- 1/8 tsp ground black pepper
Fish
- 4 pieces of cod (6 oz. each), fresh or thawed
- 1/4 tsp sea salt (or as needed)
- 1/4 tsp ground black pepper
- 1/2 tbsp extra virgin olive oil
Instructions
- Preheat oven & make the gratin. Preheat the oven to 375 degrees F. In a small food processor, blitz the garlic until minced. Add the nuts and herbs and pulse until the texture is a coarse, crumb-like texture. Next, add the cheese and pulse until just combined. (Do not over pulse to avoid making the mixture pasty). Dump the mixture into a small bowl and add the olive oil, salt, and pepper. Mix well.
- Prep and gratin the cod. Pat the cod dry with a paper towel. Place the fish pieces into a baking dish and season them with salt, pepper, and olive oil. Top each piece with a couple of spoonfuls of the gratin mixture.
- Bake and serve. Place the dish on the middle oven rack. Bake for 9-15 minutes or until the internal temperature of the fish is at least 145 degrees F and the gratin is lightly golden brown. Serve with salad and enjoy!
Notes
*Additional Recommended Products
The following items may be purchased at Kroger, Walmart, Target, or Instacart. These additional product recommendations are unpaid and unsponsored by Gourmet Garden.
Alternative: Fresh Herbs
If you are unable to find the lightly dried herbs recommended above, here are two other options and tips:
- Use fresh herbs and let them lightly dry first. Chop up some fresh herbs, spread them out in an even layer, and allow them to dry out at room temperature for a day or two before using.
- Use fresh herbs and cook them low and slow. Use fresh herbs to make the gratin and cook the fish at 350 for 12-20 minutes to allow the herbs to dry out a bit. Just keep an eye on the fish so that it does not overcook.
Nut Alternatives
Replace the walnuts with almonds, pine nuts, or pecans.
Recommended Products
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Nutrition Information:
Yield: 4 Serving Size: 1Amount Per Serving: Calories: 347Total Fat: 16gSaturated Fat: 2gTrans Fat: 0gUnsaturated Fat: 13gCholesterol: 103mgSodium: 510mgCarbohydrates: 4gFiber: 2gSugar: 0gProtein: 45g
The nutrition information provided is an estimate and will vary based on cooking methods and brands of ingredients used. I am not a doctor, nor a certified nutritionist and make no claims to the contrary. Each individual’s dietary needs and restrictions are unique to the individual. You are ultimately responsible for all decisions pertaining to your health. Please consult your personal physician with any questions you may have regarding your own health and diet.
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