How to Cook Leg of Lamb with Potatoes in the Slow Cooker. Heat oil over medium-high heat in a large skillet and brown the lamb on all sides, about 3 minutes per side. Meanwhile, add half of the garlic and the potatoes to the bottom of the slow cooker. Place lamb over potatoes and sprinkle with oregano and place remaining garlic over top.
Easily make gravy with the lamb stock (the juices left in the slow cooker – make sure you spoon off the excess fat first) after the lamb has cooked. Melt ¼ cup butter in a skillet on medium high heat. Whisk in ¼ cup flour and cook roux for 2-3 minutes. Adding a cup of lamb stock to flour and whisk until thick and smooth.
I used carrots, onions and potatoes. Put the lamb roast on top, cover and cook on low all day (about 8 hours) Or cook on high for 5 hours. Cooking times may vary depending on the size of your roast and your slow cooker. Just check to see if it's tender and to your liking.
Whether boneless or bone-in, the perfect leg of lamb should be either oven-roasted until blushing pink on the inside (with an internal temp around 130°F) or roasted long and slow for several hours until the meat is very tender and falls apart to internal temp around 175°F (I often use the slow cooker for that).