0 Preheat Traeger Grill to 225F. If you have Super Smoke, switch it on.
1 Drizzle the lamb with 1 tablespoon of olive oil and massage to coat. Generously season all sides of the lamb with salt and pepper and transfer it to the top rack of your Traeger. Smoke the lamb for 2 hours or until a red colour develops on the exterior of the meat.
2 Preheat a Dutch oven over medium heat for 5 minutes. Raise the heat to medium-high, add 1 tablespoon olive oil and heat until shimmering. Carefully add the lamb and cook, undisturbed, until browned, around 4 minutes. Flip and brown the other side, around 4 more minutes. Transfer the lamb to a bowl and set aside. If using cubed lamb meat, brown all sides, around 12 minutes total.
3 Discard all but 2 tablespoons of rendered fat in the pot. Add the carrots, celery and onion and season with a pinch of salt. Cook, stirring and lifting any brown bits off the bottom of the pot, until the vegetables are just tender, around 6 minutes. Add the garlic, fennel seeds, and chile flakes and cook, stirring, until fragrant, around 1 minute. Deglaze the pot with the white wine and cook, stirring, until the alcohol has reduced by at least ¼ in volume.
4 Return the lamb to the pot and add enough beef broth to just barely cover the meat. If using a large piece of lamb with the fat cap on, make sure the fat cap is facing up. Tie the thyme, rosemary and bay leaves together with butcher’s twine and add it to the pot. Bring the liquid to a steady simmer, cover with a lid and return the pot to the Traeger.
5 Raise the heat to 350F and cook, stirring occasionally and basting the lamb to prevent burning, until the thickest part of the meat easily pulls apart with a fork. Discard the bundle of herbs. Add the spinach and cook until wilted, around 3 minutes. Taste the ragù for seasoning and adjust with salt, pepper and chili flakes as desired. Keep in mind that if tossing the ragù with pasta, the pasta water will also be salted.
6 Bring a large pot of water to a boil. Season the water with 1.5 tablespoons of salt and add the pasta. Cook the pasta until al-dente, around 10 minutes. Reserve 1 cup of pasta cooking water and drain the pasta. Add the pasta, pasta water and ¼ cup of grated pecorino to the lamb ragù. Cook, tossing everything to coat, until the pasta is cooked to your desired doneness, around 2 minutes. Transfer the pasta to individual serving bowls, drizzle with a small amount of olive oil and top with more grated pecorino. Serve immediately.
