Smoked Mackerel, Poached Egg and Watercress on Sourdough
Twelve minutes, no knife skills, and the single best vitamin D breakfast you can buy in a British supermarket. The vinegar in the poaching water is the difference between an egg and a mess.
Ingredients
- 1 fillet of smoked mackerel, about 70g, skin removed
- 1 egg, as fresh as you can get
- 1 thick slice of sourdough
- A large handful of watercress
- A few tomatoes, halved
- Half a lemon
- 1 tsp extra-virgin olive oil
- 1 tbsp white wine vinegar, for the water
- Plenty of black pepper
Method
- Bring a small deep pan of water to a bare simmer — bubbles rising but not breaking hard. Add the vinegar. Do not salt it; salt loosens the white and spreads it.
- Crack the egg into a small cup first. Then tip it into a sieve for a few seconds and let the loose, watery white drain away. This, not the whirlpool, is what gives a neat poached egg — the whirlpool mostly just makes it spin.
- Slide the egg in and cook for 3 minutes for a set white and a liquid yolk. Lift it out with a slotted spoon onto kitchen paper.
- Toast the sourdough while the egg cooks.
- Flake the mackerel over the toast in large pieces. Squeeze over some lemon.
- Dress the watercress and tomatoes with the oil and the rest of the lemon, pile them alongside, and set the egg on top. Pepper, and no salt — the mackerel brings enough.
Why it works
At UK latitudes the sun is too low from October to March for the skin to make vitamin D at all, and very few foods contain it. This breakfast is one of them.
Smoked mackerel is among the richest food sources of vitamin D, alongside omega-3 in the long-chain form the body can actually use. Vitamin D receptors are present in the testes, and correcting a genuine deficiency has been associated with modest improvements in testosterone; adding more on top of an adequate level has not. The honest position is that this is worth eating because deficiency is common here, not because more is better.
Smoked mackerel is also salty, which is the one caution. Buy the plain smoked fillets rather than the peppered ones in sauce, and leave the salt out of everything else on the plate.
The egg and the fish together bring 26g of protein, which is what makes a savoury breakfast hold until lunch when cereal does not.
Watercress is there for dietary nitrate and for the same brassica compounds as broccoli, and it is one of the few salad leaves with a meaningful nutrient density.
More on the first meal of the day: breakfast mistakes that work against testosterone.
