Unholy Mackerel with Fennel, Apple and Walnut Salad

I love it when a plan comes together!

Since it's been a while since we put a new recipe on here and it's a (relatively) warm time of year, I thought I'd come up with a seafood dish using the underused but cheap, sustainable and delicious mackerel - no, it's not just for cat food.  The walnuts, apple and fennel compliment the meaty flavour of the mackerel with their respective saltiness, tartness and aniseediness (I just invented that word), and the vinaigrette binds it all together on the pallet.

Ingredients (for one):

• 2 mackerel fillets, pin-boned
• Half a fennel bulb
• Half a braeburn apple
• Small handful of walnuts
• About 1 tbsp olive oil, for frying
• Salt and freshly ground black pepper
• Handful of parsley leaves
• For the vinaigrette: 1 dsp cider vinegar, 3 dsp extra-virgin olive oil, salt, 1 tsp English mustard and 1 tsp honey

Method:

1. Put the vinaigrette ingredients in a bowl and whisk until they emulsify.  Check you're happy with the seasoning and then refrigerate.  This makes a bit more than you strictly need for this recipe, but it makes more sense to make this in bigger quantities and you can always use it for other salads.  It also means you can have a ready-made supply in the fridge ready for action at a moment's notice, like Chuck Norris.
2. Get a pan nice and hot.  While you're waiting, pin bone the mackerel fillets using tweezers and slice the fennel into julienne strips (matchsticks to you or me).
3. When the pan is hot, make a few very small incisions on top of the mackerel skin and season, then pour some oil in the pan and put them in skin side down.  If they don't sizzle vigorously on contact then the pan is not hot enough - take them out and wait.  Once the fillets are cooking, leave them alone and don't touch them until you can see that almost all the flesh has turned white, which should take a few minutes.
4. While the mackerel is cooking, cut the apple into julienne strips.  The reason I recommend doing that at this stage is that apple can start turning brown if it hangs around for too long.  Chop up some fresh parsley and toss all the salad ingredients together with some of the vinaigrette.
5. Get a hot plate ready with the salad on as a base.  As soon as you can see that the mackerel is almost cooked, flip it, take it off the heat and place each fillet on the salad - fish isn't hard to cook, but it will be very unforgiving if you overcook it.
6. Serve immediately with a glass of crisp, dry white wine or cider.