I can’t take credit for coming up with the idea to grind dried porcini mushrooms to make a flavourful crust for lamb. Was going to say that this was Tyler Florence’s idea but a quick search of the interwebs found tons of hits for porcini crusted lamb. Here’s the link to Tyler’s recipe that made me want to make this the first time.
My version of this recipe is slightly different. I use a bone in leg of lamb even though the bone confuses the heck out of me when it comes time to carve the beast up. The porcini crust makes the tastiest lamb I’ve ever had. It’s earthy flavours are a perfect match with lamb. I’ve tried this crust with other meats and it’s never better than with lamb. Other flavours that go well with this are rosemary and garlic so I make sure they’re in there too by cutting little slits in the roast and stuffing fresh rosemary and slivers of garlic.
Gravy gets it’s flavour in a few ways. Flavour comes from the drippings that come off the meat while it’s roasting. Each meat will lend it’s particular flavour to the gravy. If you just let the drippings hit the bottom of the pan they’ll evaporate while the roast cooks. It makes a dark stain on the bottom of the roasting pan. You can release it by deglazing the pan with wine or stock. A better option is to put something under those drippings to catch the flavour and add to it. Vegetables and herbs do a fine job of catching drippings and giving them loads more flavour. I used onions, mushrooms, garlic, rosemary and thyme. The vegetables were rolled around in the pan that I used when I was crusting the lamb so they got a light dusting of the lamb crust (waste not want not).
Once the roast was cooked I deglazed with some red wine chicken stock and poured the juice into a sauce pan leaving the veg and herbs behind. While the liquid was coming up to a boil I made a slurry of flour and water in a glass jar. It’s good to keep an old jar around for jobs like this. You can shake the hell out of the slurry to mix it up well and not worry about having the stuff fly all over your kitchen. Slowly add mix in the flower and water mixture while stirring with a whisk. Thickness is up to your taste. I like a medium thickness so I can tell it’s ready when it coats the back of a spoon. I dip a spoon in the gravy and then run my finger down it. If the line joins up again right away it’s still too thin. If the line stays where you put it then it’s thick enough. I lower the heat to a simmer and stir it occasionally while I’m getting the rest of the feast ready.
Porcini Mushroom Crust
4 oz package of dried porcini mushrooms
1 1/2 tbsp garlic powder
1 tsp smoked paprika
1 tsp kosher salt
a couple grinds of black pepper
Cut the dried mushrooms into small chunks. We have a little blender that I like to use for this sort of thing. You could use a spice grinder or some other device. The idea here is to pulverize the mushrooms into a fine powder. Dump the porcini powder into a mortar and pestle. Throw in the rest of the ingredients and grind with the pestle to break up any larger bits of mushroom that survived the grinding in the blender.
Roast Leg of Lamb
1 leg of lamb
1 medium onion
several cloves of garlic
camelina oil (not necessary but nice)
porcini mushroom crust
Take the roast out of the fridge a leave it on the counter for about an hour before you plan to cook it. Grab some paper towels and dry off the leg of lamb. Pre-heat the oven to 350 F. Put the leg in a dish or some other container that will hold the whole leg. Cut some garlic cloves into small slivers. Strip some rosemary off the branch. Cut small slits in the leg and first stuff in some rosemary and then a sliver of garlic. Flip the leg over and do it all again on the other side. Pour a good glug of olive oil on the leg and smear it around until the whole thing is glistening. Sprinkle some camelina oil on as well (not nearly as much as the olive oil). Coat the roast with the porcini crust making sure to get it all over. Cut up the onion and separate the layers so the pieces are like flower petals. Cut up the mushrooms so the pieces aren’t too big (or small). Take the roast out of the pan and throw in the onions and mushrooms. Toss the vegetables around to coat them with the porcini crust that fell off the roast while you were coating it. Throw the vegetables in the bottom of the roasting pan with some sprigs of rosemary and thyme. If there is any porcini crust left over you can sprinkle it on top of the veg. Put the rack in the roasting pan and put the roast on top of it. I have a digital meat thermometer so I push that thing in to the thickest part of the meat (being careful not to put it right next to the bone). Put the roast in the oven and set the thermometer to alarm when the temperature hits 140 – 145. My leg took about an hour and a half to an hour forty-five to cook. When it’s done remove the roast from the oven and cover with aluminum foil. It will continue to cook after it comes out of the oven and the temperature will actually rise once it comes out of the oven.
Time to make gravy. Remove the rack from the roasting pan and put it on the stove top at high heat. Deglaze the pan with red wine and chicken stock. Use a spoon or whisk to get the lovely brown bits off the bottom of the pan. Transfer just the liquid to a sauce pan leaving the veg and herbs behind. Mix the flour and water together to make a slurry. Once the liquid has come to a boil slowly mix in the slurry while whisking like mad. Once the gravy has thickened up you can reduce the heat to a simmer and stir it occasionally so it doesn’t for a skin on top or burn on the bottom of the pan.
Carve your roast and pour the gravy into a suitable container. Enjoy with friends and family.