Smoked Mackerel Gratin

I have a huge amount of love for smoked & tinned fish, it is delicious, cheap and when sealed in its packet keeps well for several weeks.    I buy my smoked and tinned fish from Waitrose as all their fish is sustainable and certified by the Marine Stewardship Council.

A few weeks ago I was lucky enough to receive a cool bag packed with Total Greek Yoghurt much of it has gone into breakfast smoothies, but I used one last pot in this gratin.

If you are gentle with it Greek yoghurt should not split if you cook with it.  I find that it occassionally does spilt, especially if you are mixing it with lemon juice, but it still tastes delicious and has the huge advantage in being considerable lower in fat than cream – I used the 2% Total in this dish,  single cream has a fat content of 18% – by my maths that is 9 Greek yoghurt gratins for the price of one creamy one, it is not even close to a fair fight!

We both enjoyed this and it is firmly on the to make again list.  Next time I will probably not put spinach in the gratin as it made it too watery and my caper obsessed mind is telling my that capers would would well stirred into the gratin too.
Smoked Mackerel Gratin (serves 2)

10oz / 225g potatoes
2 smoked mackerel fillets – skin removed and roughly chopped
150g pot 2% Greek yoghurt
1 tbs grain mustard
Sprinkling of cheese
Pepper & salt to taste
Olive Oil
Spinach leaves

Par boil the potatoes – I used salad potatoes and did not bother to peel them.     Heat the oven to 375F / 190C / GM5.   Glug some olive oil into an oven proof dish.   Add a handful of spinach then the mackerel.     Stir the mustard into the yoghurt then spread over the mish and spinach.   Drain and slice the potatoes, arrange on top of the yoghurt.    Grate some strong cheese over – I used some aged Gouda that was delicious, season with salt and pepper.    Bake until bubbling and the cheesey potatoes are turning golden.     Serve with extra spinach.