Several years ago, when slightly overwhelmed with the amount of sweetcorn being delivered in my veg box during August and September, I decided to attempt to recreate that garishly yellow, flecked-with-red, gluey relish that many of us will remember being served with beef burgers tens of years ago. I don’t know whether it’s still on sale or not.
This recipe was born out of this year’s veg-box-sweetcorn-glut a couple of months ago. Needless to say I had already made the ubiquitous annual batch of sweetcorn relish and, with mackerel making a reappearance on the stall, I wanted to try a mackerel burger with the sweetcorn relish. As the idea developed, a slaw of some description seemed to be essential, and a beetroot one was an obvious candidate.
The result of that experiment was in some ways inevitable: the mackerel burger got on extremely well with the beetroot while being rather indifferent toward the sweetcorn. The inevitability was simply that, with peppery horseradish, oily mackerel and sweet, earthy beetroot in the mix, we were back on well-trodden ground (see Peppered Mackerel with Beetroot).
You can definitely serve these burgers in baps and, along with the slaw, the pepperiness of a watercress salad is a clear winner. Oh, and chips!
One of the things I really like about this recipe is that the oiliness of the fish is all that is needed to bind the patties, without the need for egg, flour, breadcrumbs etc. that can make burgers dry and heavy. The ingredients for the burger itself are just a selection of some of the usual suspects in that they are punchy and piquant and perfect with mackerel. But there are others of a similar vein that I think are well worth experimenting with, including capers, chilli, shallot and garlic to suggest a few. I would just be conscious of the balance of quantities of mackerel to other ingredients as the patties may become difficult to form.
When it comes to cooking the mackerel burgers you probably want the oil temperature to be a touch higher than you might for an equal-sized beef burger. The reason being that, in both cases, you are aiming to get the outside golden without cooking the centre overly, but this result will achieve quicker with the mackerel.
The slaw can be made ahead of time as, over a few hours, the blend of flavours will continue to develop, but keep it in the fridge if doing so because, at room-temperature, the vegetables will start to ooze water and the slaw will lose its creaminess.
Otherwise, this is a very straightforward recipe.
Mackerel Burger with Beetroot Slaw
Ingredients (serves 2)
Sunflower oil for shallow-frying
2 mackerel, filleted, skinned and diced like coarse mince
4 tsp finely chopped gherkin, excess juice squeezed out
2 tsp chopped dill
2 tsp chopped parsley
1 or 2 pinches of grated lemon zest
Salt and pepper
1 small carrot, grated
¼ beetroot, grated
¼ red onion, finely sliced
1 tsp horseradish
2 tsp mayonnaise
Splash of cider vinegar
Method
In a bowl combine the mackerel 'mince', the gherkin, dill, parsley, lemon zest and seasoning to taste. Form into two patties and put in the fridge to set for 20 minutes.
To make the beetroot slaw mix together the remaining ingredients in another bowl with some seasoning. Taste for the balance of horseradish, vinegar and seasoning and adjust as necessary. Leave aside.
10 minutes before you're ready to fry the burgers remove them from the fridge to allow them to come to room temperature. Heat the oil for shallow-frying and cook the burgers for about 1½ minutes per side. Drain on kitchen paper and serve straightaway.
Links
Peppered Mackerel with Beetroot: https://www.butestseafoodie.com/post/peppered-mackerel-with-beetroot