Butter poached lobster with leeks and a lobster sauce

27 August 2018

Butter poached lobster with leeks and a lobster sauce

I’ve cooked lobster a couple of times in the last decade. Each time it’s been disastrous - and not just for the lobster. But it’s part of the sea’s bounty in this part of the world - so it’s really one of those things I would add to my basic rule that each time it’s in season, I should have it at least once. So I had to break the run of bad luck and get it right.

The first time, the lobster was undercooked when it was released from its shell, and I didn’t do a great job of correcting the problem. The second time, the timer failed to go off (let’s call a spade a shovel and say we assume it was human error) and the lobster ended up very overcooked. 

This time, I decided a different approach was in order. Rather than cooking the lobster in one go while still in its shell, I would steep it in hot water just long enough to be able to extract the raw meat from the shell, and then butter poach the flesh using the sous vide machine. Extracting the meat before cooking gives you a lot more control (although there are no good excuses for the original failures which, in my defence, were quite some time ago).

Cooking fresh lobster begins with the part that discourages the faint at heart - because you really need to buy the lobster still alive, and dispatch it yourself. Personally, I think it’s healthy if you decide to eat meat that, occasionally at least, you should be confronted with the full weight and implications of your decision. Not everyone agrees, and that’s just the way it is. In any case, there is a well-described procedure for killing the lobster without pain and suffering. Few natural predators would extend the same courtesy, so that’s progress of a sort. 

The real joy of this recipe is the lobster sauce. All the flavour comes from the shells and when you first taste the liquid you’ve been cooking them in, it doesn’t taste that big a deal. But then you reduce it down by around two-thirds and by then the flavour packs a punch and has glorious complexity. It’s a magical thing.

In this case, I was going for a meal that was delicious and rich but not large. A small bed of sautéed leeks and charred crushed new potatoes was all I had with the lobster (half a lobster per person). You can obviously add more substance should you wish with additional veg, or even another seafood element. Once you’ve butter poached the lobster, and made the sauce, there’s really no end of the combinations you could add that would make for a happy plate.

I’m lucky, obviously, to have the sous vide option. It enables you to poach the lobster at a very precise temperature and using a lot less butter than you would poaching it in the conventional way. I give the instructions for non-sous vide as well below, should you not be in the happy position of having your own water bath.

Lobster and sustainability

Lobster gets a different rating depending where in the UK you source it. Very generally speaking, the further north and west you go, the more you need to check. Wales, North England and Scotland have the most red flags. The upshot is that this is one that you should check the origin of very carefully, and establish its rating. If in doubt, leave it until you can identify a verified sustainable source.


Butter poached lobster with leeks and a lobster sauce

Serves: 2

1 lobster
50g butter (if using sous vide), 250g butter if not
2 tablespoons olive oil
1 carrot, chopped
1 onion, chopped
2 garlic cloves, crushed
1 tablespoon tomato purée
2 tablespoons brandy
1 glass white wine
500 ml boiling water
250 ml double cream
1 tablespoon white wine vinegar
2 leeks, white and pale green, sliced
10 new potatoes, cut in half


Heat the sous vide water bath to 60ºC.

Steep the lobster in recently boiling water for 3 minutes. Remove it, and remove the claws and put them back in the hot water for a further five minutes. You might want to use rubber gloves or a towel, because the shellfish will be hot. While it’s still hot, twist off the tail. Twist off the end fan and push the tail meat out of the larger end. Cut in half and remove the digestive tract that goes up the length of the tail near the top, if present.

After five minutes, remove the claws, crack them open using a nut cracker or similar tool, and extract the meat aiming to keep it as whole and undamaged as possible.

If using sous vide, lightly season the flesh, and then place the tail meat in the sous vide pouch, add half the butter on top, add the rest of the meat and then more butter. Vacuum seal the pouch and put to one side.

Remove the insides from the head, and then chop the shell up into medium-sized pieces. Heat the olive oil and sauté the shell over a medium high heat, stirring often, for five minutes or so. Then reduce the temperature to medium and add the onion, carrot and garlic. Fry these for a further few minutes until softened but not coloured. Then add the white wine, brandy, and the tomato purée. Simmer until the wine has been reduced by half.

Add the boiling water and simmer for 25 minutes. Then strain the lobster sauce through a fine sieve into a clean pan. If you taste the liquid at this point, you’ll probably think it somewhat underwhelming, but panic not. Simmer this liquid until it has reduced down by around two-thirds. 

While that’s doing, sauté the leeks in a small frying pan with a little oil. When they’re nearly done, add the butter and continue to cook on a low heat.

Also, put the new potatoes in to cook in a small pan of salted water. When the potatoes are soft, take them off the heat and lightly crush them with a fork or a potato masher. Put to one side.

At this point, the flavour of the sauce should be a lot more powerful. Add the double cream and continue to simmer gently.

While the sauce is thickening, put the lobster into the sous vide water bath for 8 minutes. 

If not using sous vide, add a couple of tablespoons of water to a pan and bring it to the boil. Reduce the heat and whisk in 25g of the butter until it’s all melted. Keep adding the butter piece by piece until it’s all been added. Bring the melted butter emulsion to 60ºC using a digital thermometer to check progress. When it’s reached the right temperature, add the lobster and poach - keeping the temperature constant - for 6 minutes.

While it’s in, check the sauce and adjust the seasoning with salt and the white wine vinegar. Remove the leeks from the frying pan and keep warm. Add a little fresh oil to the pan and put in the crushed potatoes, seasoning them lightly with some salt as you do so.

Once the lobster has been poaching for 8 minutes, it’s time to serve. Using a food ring, place a circle of the sautéed leek, and top with the crushed potatoes. Add half of the tail meat, then the rest of the meat, topped by the claw. Spoon the sauce around the plate, with a little drizzled on top of the lobster. Garnish with a little parsley if wished, and serve.

Food waste

As ever, when using double cream, if you have some left and don’t know quite when you’ll use it, you can freeze it for future use. This only really works if it’s double cream. 

I’m assuming you don’t need ideas from me on what to do with the rest of the bottle of white wine …