You begin with the meat. Classically speaking, this is a veal roast (see Notes below for the common cuts). But you can economize by using pork loin or—my favorite—pork tenderloin or turkey breast instead. Whichever you choose, prepare a kind of court bouillon by simmering the onion, carrot, celery, bay leaf, cloves, salt and whole peppercorns in a mixture of white wine and water, about a glassful of wine and just enough water so that the liquid will entirely cover the meat when it is placed in the pot. (To be sure, you can place the meat in the cold liquid beforehand to see if there is enough liquid.)

After the aromatics and liquids have simmered for about 10-15 minutes, add the meat, raising the heat if need be to keep the water simmering nicely but it should not boil, which would toughen the meat. I cover the pot partially to reduce evaporation. Simmering time will depend on the meat you use, but the classic recipes call for cooking the veal roast around 60-90 minutes, depending on the size and the cut. (The original cuts were suitable for long simmering, modern recipes often call for loin, which should be just cooked through.) Pork loin should take about 60 minutes or less, while the tenderloin, which is quite a 'skinny' piece of meat, should take no more than 20-30 minutes. Turkey breast should take about the same as pork tenderloin.

Remove the pot from the heat and allow the meat to cool completely, still immersed in its cooking liquid. This should take about an hour or so, and it results in a moister and more flavorful meat. But if you are in a hurry, you can remove the meat from the liquid and place it in the fridge to cool down quickly.

While the meat is cooling, it is time to turn to the sauce. You begin by making a mayonnaise in a blender: place the two whole eggs (not just the yolks) in a blender with the juice of half a lemon and pinch of salt.

Then turn on the blender to 'purée' and let it go for just a few seconds. The egg mixture will have turned frothy:

Now turn the blender on again and, with the little clear plastic 'window' in the lid removed, starting pouring in olive oil little in a slow but steady stream, until the eggs and oil emulsify and you get a nice, thick and creamy mayonnaise. I believe that the classic proportions call for one cup of oil per egg, but I usually 'eyeball' it and stop when the mayo is nice and thick.

By the way, this is one case where so called 'light' olive oil may be better than the dark green fruity kind, which would give the sauce a too strong olivey taste. Or you can use Provençale olive oil, which is more delicate.In any event, once your mayo is ready, add a fillet or two of anchovy, a spoonful of capers and a can of tunafish (preferably packed in olive oil). Blend again until smooth.

Then temper the sauce with a couple of spoonfuls of the meat cooking liquid, enough to produce a pourable but still quite quick sauce. Transfer to a bowl.When the meat has achieved room temperature, remove it from its broth, pat it dry and place it on a cutting board. Slice it against the grain into thin slices.

Now take each slice (you'll probably need to do this by hand, otherwise use tongs) and dip in on each side in the tuna sauce and arrange the slices on a platter, each slice just slightly overlapping like so many roof tiles, in an attractive pattern. While pork tenderloin, there will be room for several rows of meat.

Other cuts are larger, so you will probably need to make a single row or arrange them in a circular pattern on a large platter.Finally, finish the dish off by pouring over the top the remaining sauce. While you can serve the dish right away, it develops better flavor if you let it sit for several hours, overnight or—in some recipes—for a few days, so the flavor of the tuna sauce penetrates the meat completely. Before you are ready to serve, garnish the dish with capers and, if you like a more elegant presentation, some thin slices of lemon around the edges and some parsley leaves.