FRESH, milky-white, flaky cod fillet is a delicious meal. For years, we undervalued this cheap and plentiful fish. Frozen in bulk, turned into boil-in-the-bag meals, fishcakes and ubiquitous fish fingers, it appeased our modern appetite for fast food. Ready to eat in seconds, these dishes required no preparation and very little thought.

Over-fishing made us prize fresh cod more highly. Atlantic cod is back on the sustainable fish list and in season right now. When sparkling fresh, it's a superlative fish, comparable with other prime species such as wild halibut and turbot.

We should all eat much more fish. In generations past, Scotland consumed far greater quantities of fresh fish than today, and our high streets boasted many fresh fishmongers, so the quality of produce available was second to none.

If you have a local fishmonger, I implore you to shop there more often and seek their advice on what to buy and how to prepare it. Like local butchers, fishmongers are highly skilled specialists in their craft.

For generations, women from our fishing ports, walked miles inland and throughout the towns and cities, selling fish from the packed creels they carried with them. Sometimes exchanging goods from the countryside for their coastal treasures, Scottish fishwives were frequently seen around as recently as my own childhood. The fish vans that took over their role remain prevalent today and are recommended if you don't have a local fish shop.

Supermarkets try to provide the same level of service as a local fishmonger, but they'll never be quite the same. With numerous vacuum-packed alternatives sitting in refrigerated cabinets alongside the fresh fish on open display, some large stores could be criticised for being half-hearted in selling this wonderful, nutritious ingredient.

Specialist port-based wholesalers offer a new means of buying fresh fish online, and delivering chill-packed produce very quickly to your door, and worth considering if you haven't a local fishmonger.

One of my earliest encounters with local Skye fishermen was the appearance of two swarthy characters at the restaurant’s kitchen door. It was February 1985, just two months before we embarked upon the real life of restaurateurs. I spent those first winter months, honing new skills and the men at my door were about to present me with yet another learning opportunity.

They had some huge, beautiful whole cod in a wooden fish box, which they'd brought ashore at Colbost. They would freeze well and make a great dish for when we opened at Easter. Would I like to buy them?

I seized the moment and agreed a cash price. They left happy – and I was about to become a lot wiser. The domestic cooking knives I'd brought with me were all I had available to prepare the fish. I quickly realised I needed to invest in far better tools. Cutting through the backbone to remove the head was almost impossible and I struggled to cut away the hefty fillets. Once started, there was no going back and I soldiered on. My hands were freezing cold and my shoulders ached. I had cut myself and felt hopelessly inadequate, despairing at why on earth I'd ever imagined I could run a restaurant.

I probably wasted more of those prize specimens than I should have done, but I was proud of what I packed away in the freezer and I made my first enormous pot of fish stock. Both cod and stock were put into use on our opening menu, although the success of both dishes is yet another story of a greenhorn attempting to cook professionally.

Fresh fish became a mainstay of The Three Chimneys menu, along with the superb creel-caught and hand-dived seafood for which Skye and the west coast of Scotland are renowned.

When we Scots choose to eat out, we often choose fish, because the restaurant does all the work, presenting us with a perfectly cooked dish to enjoy. Fish and chips is considered a national dish and we buy it as a treat in great quantities. It seems ironic that the popularity of fish does not often extend to preparing it for family meals. Our continental neighbours eat far more than we do, frequenting fabulous local fish markets to select the best. While on holiday, we love to visit these markets too, to goggle at the amazing displays and enjoy the stallholders' raucous banter as they sell their wares. Why do we hesitate from doing the same when we return home?

February is a wonderful month to choose fresh cod. Seville oranges are also in season and they make a delicious sharp sauce to accompany white fish of many kinds.

This is a "cheat’s" way of making Hollandaise sauce and you can use the same recipe for coating poached eggs for Eggs Benedict or Eggs Florentine, or serving with fresh asparagus.

Fresh cod with Seville orange butter sauce

(Serves 4)

For the fish:

4 pieces of fresh cod fillet

25g unsalted butter

Zest of ½ of 1 medium/large Seville orange, plus 2 slices of the whole fruit cut into smaller pieces, plus juice of what remains of ½ orange

4 large sprigs of flat-leaf parsley

Sea salt and ground black pepper

For the sauce:

3 large eggs, yolks only (freeze the whites in a clean container for making meringues at a later date)

2 tbsp freshly squeezed Seville orange juice

1 tsp cider vinegar or white wine vinegar

Freshly ground sea salt

150g unsalted butter

4 tsp double cream for re-heating the sauce (optional)

Method

1. Using half the butter, grease an ovenproof dish large enough to contain the cod in a single layer. Scatter the zest and pieces of orange over the base. Break up the parsley roughly and scatter in the dish. Season with salt and pepper. Squeeze a little of the orange juice over the base of the dish. Lay the pieces of fish on top of the above ingredients. Sprinkle each piece with a little more salt, plus a dab of butter and a squeeze of juice.

2. Cover with foil and set aside until ready to cook in the centre of the oven at 180C for 15-20 minutes, depending upon the thickness of the fish. Time your accompanying vegetables, accordingly.

3. To make the sauce, place the egg yolks, orange juice, vinegar and salt in a blender and whizz for a few seconds to mix.

4. Melt the butter in a small saucepan, preferably one with a pouring lip. Turn off the heat and allow the white solids to sink to the bottom of the pan.

5. Remove the centre piece from the lid of the blender. Pour the warm melted butter over the egg mixture, through a small, fine sieve or strainer, ensuring that the white solids don't mix with the egg. The blender should be running on a slow speed while you are pouring the butter into the egg mixture in a thin, steady stream. Serve immediately, or alternatively, transfer the sauce into a small bowl or jug for reheating before serving.

6. If you choose to reheat the sauce, add one teaspoon of cream per person while reheating. Whisk thoroughly before pouring over the fish on the plate. Reheat the sauce in a bowl over a saucepan of hot water for a few minutes. Alternatively, add the cream and heat for a few seconds in a microwave. Whisk thoroughly to avoid splitting the sauce. If it splits, add a splash of very cold water and whisk again.

Shirley Spear is owner of The Three Chimneys and The House Over-By on the Isle of Skye. See threechimneys.co.uk