Trim any access fat off the diced lamb. Pat them dry with a paper towel. Season with salt and pepper.
1 tbsp olive oil, 1 1/2 lb diced lamb
Heat the oil in a large pan Dutch oven over high heat. Add the diced lamb and cook until it is browned on all sides - about 4 minutes. Make sure not to overcrowd the pot or the meat will stew instead of gaining color. Sear the meat in two lots if needed. Remove it from the pot with a slotted spoon and set aside.
Add the diced onion, carrot, and celery. Cook for 5 minutes until softened. Add the minced garlic and cook for 1 minute until fragrant.
Deglaze the pan with red wine (or beef stock). Let it cook down for 3 minutes on high before adding the crushed tomatoes and stock. Bring everything to a boil and reduce the heat to a gentle simmer.
1/2 cup red wine, 28 oz tomato puree, 3/4 cup beef stock
Add the bay leaf, thyme, rosemary, and ground black pepper alongside the browned meat. Add the lid and transfer it to the oven and cook for a minimum of 2 hours. Alternatively, simmer it on the stove on low heat.
1 bay leaf, 1/2 tsp dried thyme, 1/4 tsp dried rosemary, 1/2 tsp ground black pepper, 1 tsp salt
Remove the lamb ragu from the oven. Discard the bay leaf. Let it sit for 5 minutes to allow the meat to relax a little before shredding the meat with two forks.
Meanwhile boil the tagliatelle in salted water until they're almost al dente as the pasta will continue to cook slightly in the hot sauce. Reserve a cup of pasta water to loosen up the sauce if needed.
12 oz dried tagliatelle
Drain the pasta and add it straight into the ragu. Toss to combine the two. Add a little pasta water if needed to loosen up the sauce, especially if the dish sits for a few minutes.
Serve immediately with some fresh mint.
2 tbsp fresh mint
Notes
Meal prep: The ragu actually tastes better the next day as the flavors continue to develop. A perfect make-ahead meal!Sear lamb: Make sure to brown the seasoned lamb well to lock in all the juices and create an intensely flavored sauce.Add pasta to sauce: Once cooked, add the tagliatelle straight to the ragu instead of serving them on top of each other. This way the pasta absorbs the rich ragu without clumping up and helps thicken the sauce.Storage: Store the lamb ragu sauce in the fridge for up to 4 days or freeze it for up to 3 months. Simply defrost and fully reheat it.