Cook the orzo in boiling salted water according to the package instructions, then drain and set aside.
In a medium bowl, combine the ground lamb with the dried oregano and half of the garlic powder, sea salt, and black pepper.
Form the lamb mixture into small 1-inch meatballs.
Heat the olive oil in a large skillet over medium-high heat and sear the meatballs for 8-10 minutes until golden brown and cooked through.
Remove the meatballs from the skillet and add the spinach to the same pan, sautéing until just wilted.
Toss the cooked orzo with the wilted spinach, lemon zest, lemon juice, and the remaining garlic powder.
In a small bowl, stir the Greek yogurt with the remaining salt and pepper to create a smooth sauce.
Serve the lamb meatballs over the lemon-herb orzo, topped with crumbled feta cheese, fresh parsley, and a dollop of the yogurt sauce.