Smoked Haddock Gratin (Fish Pie with Smoked Haddock)

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A slight twist on a traditional British Fish Pie. Our Inverted Fish Pie with Smoked Haddock has a layer of potatoes and spring greens at the bottom of the dish and is topped with fish fillets and a cheesy mustard sauce! Smoked Haddock Gratin is a wonderful dinner dish for those Fish Fridays!

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What’s Smoked Haddock Fish Pie All About

Fish pie has long been a favourite of Seb’s. We make our traditional fish pie with a fish pie mix (salmon, haddock and smoked haddock), creamy roux flavoured with nutmeg, hard-boiled eggs, garden peas and mashed potato topping. But with haddock in season between November and April, we found ourselves eating quite a lot of it lately. What is more, some people we know are following traditions not to eat any meat on Fridays, and although we are not strict on the rules, fish is generally preferred to meat by both of us on any day of the week.

One of the meals that we seem to be coming back to most often is our Inverted Fish Pie with smoked haddock and spring greens. It is less calorific than our traditional Fish Pie (a portion is just under 500 kcal) and more suitable for lighter dinners in spring. The addition of spring greens makes it even more seasonal!

We like to call this fish gratin an Inverted Fish Pie. Why? Well, simply because we put the potatoes in the bottom of the dish, then a layer of spring greens and then fish. We top it all with breadcrumbs. So our Fish Pie is truly upside down!

A spoon in a creamy smoked haddock gratin sauce after a qaurter of the pie has been served.

Recipe FAQ:

Can I Use Frozen Smoked Haddock?

Absolutely. When fresh haddock is not in season, simply defrost the haddock and continue with the recipe as normal.

What Can I Substitute Spring Greens With?

This Smoked Salmon Gratin is simply wonderful with spinach or swiss chard! Alternatively, you can use kale, but make sure to get rid of any tough stalks.

Why Does the Recipe Require Two Types of Mustard?

We use Dijon mustard for flavour – it adds a gentle mustard heat to the dish. Wholegrain mustard is perfect for its texture – you get little popping balls with every mouthful. And the sauce looks pretty and inviting! If you only have one type, just use what you have.

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How to Make our Smoked Haddock Fish Pie?

Peel and cut the potatoes into 1cm thick rounds and boil them in salted water until just tender (but not falling apart). Drain carefully trying to keep their shape. Once they are cool enough to handle, arrange them in the bottom of an ovenproof dish.

Preheat the oven to 190°C Fan. In a small saucepan, on medium heat melt half of the butter. Add the flour and a pinch of chilli powder (or cayenne pepper). Stir continuously for approx. 1 minute to make a roux (a pastelike mixture). Little by little, start adding the milk, stirring to avoid lumps from forming. Some say a secret to no lumps is to heat the milt first and add the hot milk to the flour and butter, but I never struggled by simply adding cold milk gradually. When it starts simmering, reduce heat to low and simmer for 3-5 minutes to thicken (it should look like your usual bechamel/ white sauce).

Take the sauce off of the heat, then add dijon and wholegrain mustard and half the chopped chives. We use Dijon mustard for flavour and wholegrain for texture. If you only have one type, just use what you have. Add about ¾ of the grated cheddar. Stir gently until the cheese melts and the sauce is smooth.

In a large frying pan with a matching lid, melt the remaining butter. Add the spring greens, cover and cook for 2-3 minutes until just wilted and softened. Spoon the greens over the potatoes in the ovenproof dish. Place smoked haddock fillets on top, then spoon the cheese and mustard sauce over the top.

Potatoes and spring greens are topped with four fillets of smoked haddock.

Sprinkle the top with breadcrumbs and the remaining cheddar. Bake for approx. 20 minutes until the top turns golden and the fish is cooked through. Sprinkle the Smoked Haddock Gratin with the remaining chopped chives and serve!

What to Serve with Fish Pie?

Whilst there are plenty of healthy greens in the haddock gratin itself, we always fancy a salad or some cooked vegetables on the side. Some of our favourite side dishes to any fish pie include:

Smoked Haddock Bake isplaced on a wooden table with a serving spoon ready to be served.

Other Fish Recipes

For other ideas for Fish Friday meals, have a look at some of our favourite fish recipes below:

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