How to Make It
Combine the garlic, oil, rosemary, cumin, and 1 teaspoon each salt and pepper in a small bowl. Rub the spice mixture all over the lamb and place in a 5- to 6-quart slow cooker along with 1/4 cup water. Cook, covered, until the lamb is tender, on low for 7 to 8 hours or on high for 4 to 5 hours.
Let the lamb rest for 20 minutes before slicing against the grain. Stir the chickpeas and spinach into the juices in the slow cooker until the spinach is wilted.
Serve the lamb over the chickpeas, spinach, and juices, with a spoonful of yogurt on top.