Serves 4

As a child my friends and I had great fun catching mackerel from the end of the pier. We did it all summer into September. The fish should be eaten within a couple of days of being caught, so if you haven't caught them yourself and are buying from the fishmonger, check them over and make sure their eyes are glossy and gills are bright red. If the fishmonger gives you a funny look for prodding the fish take no notice. When they're really fresh, mackerel are great, but they aren't considered a luxury and so they're cheap. They're good for you, too. Mustard sauce goes equally well with herrings, which are also relatively inexpensive and healthy but becoming scarce these days.

My Gran used to split the mackerel I'd caught and fry them lightly floured to give the skin a delicious crisp texture. Any spare fish would be soused in vinegar, though she never actually made mustard sauce.

4 whole mackerel weighing about 400g each, beheaded, fins trimmed, split like a kipper
Flour for dusting
Salt and freshly ground white pepper
Vegetable or corn oil for frying
A good knob of butter

for the sauce

4 small shallots, peeled and finely chopped
1tsp English mustard
2tsp grain mustard
2tbsp white wine vinegar
1tbsp double cream
1tbsp chopped chives
60g cold butter, diced

Snip out the mackerel bones with scissors if you prefer to serve it without them. Heat a couple of tablespoons of oil in a large, heavy frying pan. Season and lightly flour the mackerel and cook, skin-side down first, for 3-4 minutes on each side. You will probably need to do this in two batches depending how many you're cooking and how big your frying pan is.

Meanwhile put the shallots in a pan with the vinegar and a couple of tablespoons of water, and simmer the shallots for 2-3 minutes until the liquid has reduced by half. Add the two mustards and cream and simmer for another minute, then whisk in the butter until well mixed. Add the chives and season.

Serve the mackerel skin side up and the sauce poured on the plate or separately. New potatoes and purple sprouting broccoli go perfectly with this.