Easy Fish Gratin (Gluten Free)

This cheesy cod gratin is the kind of cosy, family friendly dish that feels both nourishing and a little indulgent. It's the perfect week night dinner, yet tasty and impressive enough if you have family and friends over for dinner.

I opted for a gluten free sauce, making it with double cream which has a wonderful velvety texture, and thickening it with cornflour. I also like to add a touch of mustard along with a strong cheddar, to flavour the sauce.

Recipe ingredients

Find the full list of ingredients and quantities in the recipe card below.

• Butter - I like to sauté the leek in salted butter, which adds to the flavour of the dish.
• Vegetables - I add sauteed leek, fresh cherry tomatoes and frozen garden peas to the dish, which all pair really well with fish.
• Fish - use any variety of white fish in this recipe, I opted for cod loin fillets.
• Breadcrumbs - I've used gluten free breadcrumbs to top the gratin. You can use regular breadcrumbs if you're not gluten intollerant.
• Garnish - I like to garnish the gratin with freshly chopped chives or spring onions just before serving.

Gluten free cheese sauce ingredients

• Cream - I use double cream (heavy cream) for the base of this sauce.
• Mustard - I flavour the sauce with Dijon mustard which is gluten free.
• Cheese - I use extra mature cheddar cheese in both the sauce and also mixed into the breadcrumbs to top the gratin.
• Thickener - I thicken the sauce with cornflour.
• Seasoning - I season the sauce with a little sea salt and some freshly ground black pepper.

How to make fish gratin

• Preheat the oven to 180C/160CFan/360F.
• Place the butter into a small saucepan over medium-high heat and allow to melt. Add the sliced leeks and sauté gently for 15 minutes.
• Layer the cooked leeks into the bottom of the baking dish, place the fish fillets on top and scatter the cherry tomatoes and garden peas around the fish.

• While the leeks are cooking make the cheese sauce. Pour the double cream into a small saucepan and heat up gently over medium heat, stir through the mustard.
• Mix the cornflour with a little water to make a paste and add that to the warm cream and keep stirring until the cream thickens to a sauce.
• Now add 100g (approx 1 cup) of the cheddar cheese to the sauce, setting the remaining cheese aside. Keep stirring until the cheese has melted, season with salt and black pepper then take off the heat.
• Pour over the cheese sauce over the fish. Mix the remaining cheese with the breadcrumbs and spread over the top of the dish.
• Place the fish into the hot oven and bake for 20-25 minutes if using fresh fish, 30-35 minutes for frozen fish, until the fish has reached an internal temperature of 63C/145F.
• Note - cooking times will vary depending on the size and thickness of the fish used.
• Remove from oven and serve immediately.

Recipe variations

• Fish - I used cod loin in this recipe, but you can use your choice of boneless, skinless fish fillets. Use fresh or frozen fish, try cod, smoked cod, hake, coley, haddock, smoked haddock.
• Shellfish - add some shellfish to the dish, try scallops or a handful of king prawns.
• Vegetables - you can use any other veggies in with the fish, try garlic, spring onions, red onion, green beans, carrot, courgette (zucchini).
• Cheese - I opted for an extra mature cheddar cheese but you can use any strength of cheese, just look for a cheese that melts well. You could also try Parmesan or gruyere.
• Mustard - as this is a gluten free cheese sauce, I used Dijon mustard. However, if you don't need it to be gluten free you can also use wholegrain or English mustard.

Serving suggestions

I've like to serve this cod mornay with a potato side and some extra vegetables. Try some boiled new potatoes, or my Easy Fondant Potatoes or Sauteed Potatoes.

I also always serve a green vegetable with this dish, try some steamed green beans, Oven Roasted Asparagus, or this Lettuce & Herb Salad.

Useful hints and tips

1. This recipe works equally well with both fresh and frozen fish, you'll just need to adjust cooking times.
2. I always keep a store of frozen fish in the freezer, it cooks quickly so ideal for busy weeknight dinners.
3. Allergy advice: gluten free, egg free, soya free and nut free. For comprehensive and detailed allergy advice go to Allergy UK.

FAQs

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Additional recipe suggestions

These fish recipes are ideal for busy week night dinners:

• Easy Fish Pie
• Oven Baked Salmon with Parma Ham
• Smoked Salmon Pasta
• Hake with a Lemon Cous Cous
• Mediterranean Fish Soup
• Simple Smoked Haddock Kedgeree
• Omelette Arnold Bennett

Looking for inspiration for feeding the family mid week, then take a look at my Ultimate Guide to Family Dinners, which is full of useful hints, tips and recipe suggestions.