Preheat oven to 375.

Prepare the orzo according to the directions on the package. Drain and set aside.

Meanwhile, set an oven-safe pan (preferably cast iron) over medium heat. When the pan is nice and hot, add the lamb. Cook the lamb, breaking it up with a spoon until it is browned and cooked through, about 5 minutes. Remove from the pan, leaving any drippings that have rendered, and set aside. Add the onion, fennel, and garlic to the pan. Cook for 5 minutes, or until softened and golden brown. Add the oregano, tomatoes, wine, cumin, cinnamon, and tomato paste. Cook for 10 minutes, stirring occasionally until the tomatoes have cooked down into a thick sauce. Add the cooked lamb, spinach, and feta. Stir until the spinach has wilted. Stir in the prepared orzo. Sprinkle the Asiago over the top.

Bake for 20 minutes, or until the cheese on top has melted and the sauce is bubbling hot.