I love this main course – which requires only two dishes to prepare – because with no more time and effort, you can make it to serve from two to eight people (you can make it for more, but you’ll need to use two roasting pans, and most home ovens aren’t large enough for that).
What’s most important is that the roasting pan is of an appropriate size; if it’s too large, the ingredients might get burned from too much exposure, but if it’s too small, the ingredients will be crowded and will steam rather than brown.
Roast rack of lamb with potatoes, petits pois and crème fraîche
I count on each rack of lamb (six to eight ribs) to serve two people, but if your guests have large appetites, they will serve fewer. (You can always serve more potatoes and peas; few people will be rude enough to demand more meat.) This recipe makes enough to feed six.
If you see fresh fava beans in the market, use them instead of (or in addition to) the petits pois: remove the pods, blanch the beans, then take off the tough peel before proceeding with the recipe.
To ensure the meat is cooked to your liking, you need a meat thermometer, preferably an electric one that you can programme to go off when the lamb is done.
Lamb racks are usually sold “frenched” – with the meat from the upper part of each bone scraped away, for tidier eating. If the rack hasn’t been frenched, have the butcher do it, or prepare the ribs yourself with the aid of a paring knife.
3 lamb racks (each from 500 grams to 750 grams), about the same weight
1kg small potatoes, preferably fingerlings or ratte
12 garlic cloves, unpeeled
600 grams petits pois, thawed, if frozen
About 80 grams of rendered chicken fat, lard or olive oil (in that order of preference)
Fresh thyme leaves
About 80 grams crème fraîche
Fine salt and freshly ground black pepper
Sprinkle salt over the lamb racks, using more on the meatier portions. Leave at room temperature for about two hours, or (preferably) in the fridge for longer.
About an hour before you want to cook the meat, preheat the oven to 250 degrees Celsius. If the meat has been refrigerated, take it out of the fridge. Put the potatoes in a pan of salted water, bring to the boil then simmer until they are tender enough to be easily pierced with a paring knife, but still firm.
Use a slotted spoon to remove the potatoes, then put them in a colander to drain. Add the garlic cloves to the same water, simmer for five minutes, then add them to the colander holding the potatoes. Briefly rinse the ingredients with cold running water. If the potatoes are too large, cut them in half.
Very lightly oil a roasting pan that is big enough to hold the racks of lamb side by side without crowding. Place the pan over the high heat of an oven burner, moving it around so it heats evenly. When the pan is very hot, put the racks of lamb fat side down in the pan and sear them. Leave them for several minutes, or until the fat is well browned. Turn off the flame and remove the lamb from the pan, putting the racks fat side-up on a cutting board. Sprinkle thyme leaves over the meat.
If using chicken fat or lard, put it in the hot pan (no need to wash it) and let it melt, then add the potatoes and garlic cloves. Mix well so the ingredients are lightly coated with the fat. If using olive oil, put the potatoes and garlic cloves in the pan, drizzle with the oil and mix well.
Whatever fat you use, sprinkle salt over the ingredients and stir, then slide the roasting pan into the oven. Cook at 250 degrees for about 20 minutes, stirring occasionally, or until the potatoes are crusty and brown.
Insert the probe of a meat thermometer into the meatiest part of the smallest lamb rack, making sure it does not touch the bone. Set the thermometer for 55 degrees (for medium-rare; or higher if you like the meat medium to well-done). Put the lamb racks in one layer in the roasting pan, placing them over the potatoes.
Roast until the meat is done to your liking, then remove the pan from the oven. Transfer the lamb racks to a cutting board and leave to rest for 10 minutes. Scatter the peas into the pan over the potatoes, then put it back in the oven and cook for five minutes. Take the pan from the oven, add the crème fraîche and mix with the potatoes, garlic and peas. Sprinkle with freshly ground black pepper and stir again.
Sprinkle black pepper over the lamb, then carve it into pieces by cutting through the ribs. Serve immediately.