Most of us cook lobster in a straightforward way, usually by plunging it in boiling water for a few minutes and then serving it with drawn butter. Occasionally we split the tails in two and broil them.
Both of these techniques makes sense when expediency is the primary goal and when we wish to eschew the complexities of French sauce making. However, to extract the most flavor out of a lobster, other techniques and processes are needed.
It helps to remember that the flavor of lobster is in three places—in the flesh (obviously), in the shells, and in the coral/ “tomally.” Different techniques are required to get the flavor out of each.
Much of the flavor of the flesh is released in the form of flavorful juices that it releases when it gets hot. If the lobster is being boiled in a pot of large water, these juices release into the surrounding liquid and are lost. An alternative is to steam the lobster in a little wine, water, or vegetable broth and then convert the steaming liquid (which will now contain the juices from the lobster) into a sauce. I usually do this with some finely chopped parsley, a drop of cognac, sometimes a little tomato puree, and a bit of butter or a little cream.
More complex approaches will also require you to get the flavor out of the shells. This only makes sense in situations when you’re serving the lobster out of the shell or at least when you have access to shells from other dishes. When extracting the flavor from lobster shells, remember that the flavor and color in the shells is not soluble in water, but instead is soluble in fat. For this reason, making a lobster broth by simmering the shells in water does little to extract the flavor. Fat must be used to extract the flavor.
One method is to cook the broken-up shells in hot olive oil (assuming they haven’t already been cooked) with perhaps some shallot and some tomato. Once the shells are bright red, cream is then added to the mixture and the mixture simmered for an hour or so—liquid added from time to time to compensate for evaporation—so that the fat in the cream can extract the flavor and colorful components from the shells. During this simmering with cream, the cream typically breaks and separates into clear butterfat, at this point bright orange-red, which floats to the top where it can be skimmed off. This lobster butter can then be used to finish a lobster sauce or sauces for other dishes where a crustacean note is appropriate.
You can also extract the flavor from the shells by crushing them together with butter. Here’s the method: Take enough shells to come about 2/3 high in a home stand-up mixer bowl and combine them with 3 sticks of cold unsalted butter. Put the mixer on low (use the paddle blade) and grind together the shells and the butter until the shells break up and the butter turns pink, 20 to 30 minutes. Transfer the butter/shell mixture to a saucepan and bring it to a gentle simmer over low heat. Cook over low heat for about 15 minutes. The butter should sputter and by doing so let you know that it still contains some water. This water prevents the butter from getting too hot and burning so when it evaporates and you no longer hear the sputtering, remove the butter from the heat so it doesn’t burn. Add enough warm water to the pan so the butter is floating above the water. Chill the mixture until the butter congeals on top of the water and shells. Take the butter off the top of the water, melt it and strain it. It keeps for weeks in the fridge or even longer in the freezer.
Perhaps most important, the most intense flavor of lobster is contained in the coral (in female lobsters only) and tomally. When buying your lobster, ask for at least one female (it isn’t necessary to be greedy and have all females) to provide coral. The coral consists of miniscule eggs, dark green as to be almost black, that turn orange when heated. The tomally consists of the liver, is a dull green, and while it has an intense, delicious flavor, it retains its somewhat drab green color even during cooking.
There are a couple of ways of going about using the coral to flavor your sauce. Most typically it is used when the lobster is cut up alive. There are two ways to assassinate a live lobster. One is simply to split it lengthwise. Another is to make a cut into the head to kill it instantly and then twist off the tail and snap off the claws. The remaining carapace commonly called the head is then cut in half lengthwise and the gritty grain sack removed and discarded. Once the lobster is in pieces, it’s easy to get at the coral and tomally by simply reaching into the tail and into the sides of the “head” and pulling them out. They should then be worked through a strainer into a small container containing a teaspoon of cognac to prevent the coral mixture from clotting. This mixture should be kept ice cold—it’s very perishable—for up to several hours before serving the lobster and using it to finish the sauce (more about this below).
If you don’t want to cut up your lobster alive you can steam it, section it and remove the coral after cooking. This makes a lot of sense since when lobster is cooked correctly, the coral remains dark. It can be pulled out, strained, and used in a sauce based on the steaming liquid.
If you’ve gone to the trouble of extracting these various flavor sources from the lobster, you’re going to be able to create a fantastic sauce. There are innumerable variations but typically the cut-up lobster is either sautéed or steamed and the meat extracted from the shells and reserved while the sauce is being prepared. Cut up the lobster, brown the pieces in olive oil or steam them with a little wine, turning them around now and then with tongs, until completely orange. It’s imperative at this point not to overcook the lobster. Once the shells have reddened, the under-cooked meat is extracted and reserved. (Lobster flesh is impossible to remove from the lobsters while they’re raw because it’s gelatinous and clings to the shells.) The coral is removed and strained and used for the sauce.
The sauce should be constructed in phases. First, any liquid such as the steaming liquid from the lobster or liquid released during sautéing can be strained into a saucepan and heated. Flavorful ingredients such as tomato puree, cognac, various wines can be added at this point. Cream almost always comes into play as an agent to tie together disparate flavors. Once the base is constructed, you can use your lobster butter by simply whisking a tablespoon or two (to taste) into the sauce. Finally, whisk the hot sauce base into the coral in a bowl and transfer the mixture back to the saucepan (ideally the saucepan should have sloping sides to prevent curdling in the corners). Heat the sauce while whisking until it turns a brilliant orange. At this point you can add chopped herbs such as parsley, tarragon, or chervil. Consider garnishes such as wild mushrooms, braised fennel wedges, boiled French string beans (haricots verts), or sweated julienned vegetables. (I once worked at a restaurant where we made a sauce americaine by simmering Cognac with a little tomato and whisking in a little lobster butter. Simple and not half bad.)
One of the most complicated aspects of cooking lobster is the need for a lot of work at the last minute, especially if you’re serving the lobster out of the shell. Taking the meat out of the claws takes a minute and is messy. While no doubt heretical, I sometimes cook the lobster ahead of time (in any case I cook lobster much less than is customary) and reheat it just before it’s time to eat. To reheat it, spread the pieces out over a buttered sheet pan and cover them firmly with plastic wrap. Heat in the lowest possible oven. Keep an eye in case the oven is too hot.