How to Make It
Preheat the oven to 400°. In a large bowl, combine the lamb, egg, harissa, parsley, garlic, shallot, salt and cumin.
In a small food processor, pulse the oats until coarsely ground. Add to the bowl. With clean hands, mix the lamb with the other ingredients until loosely combined. Avoid overly breaking up the meat. Form the mixture into 1 1/2-inch balls (an ice cream scoop works well for portioning) and roll in your hands until round and smooth. Arrange the balls on a parchment paper-lined baking sheet and bake in the oven until cooked through and beginning to brown on the bottom, about 25 minutes.
Meanwhile, in a small mixing bowl, whisk together the ingredients for the yogurt sauce.
Serve the meatballs warm or at room temperature alongside the yogurt sauce.