Heat the butter and oil in a large heavy-based casserole dish set over a medium heat. Once hot, add the rabbit and fry until browned on all sides, c. 5 minutes. Remove with a slotted spoon and set aside.
Add the pancetta with the herbs and chopped onion, garlic, celery and carrots. Give everything a good stir and cook gently for c. 10 minutes until the onion is getting translucent.
Then add the white wine, stock and passata and bring to a simmer. Return the rabbit to the pan, reduce the heat to low and cover. Cook the ragù for about 50 minutes, stirring occasionally and adding more stock if the liquid reduces too quickly. At this point, using two forks, shred the rabbit meat from the bones and return the meat to the pan, discarding the bones.
1 hour, . By the end you should have a red-blushed, thick sauce with meat that almost falls apart. Taste and adjust the seasoning; discard the sage and rosemary, remove from the heat and set aside
Next, bring a large pan of salted water to a rolling boil. Lower in the tagliatelle and cook for 3–4 minutes
Meanwhile, put the rabbit ragù back on the stove over a medium heat. When the pasta is ready, drain it and top with the ragù. Toss until any water has been absorbed and the pasta is well-coated with the sauce. Serve with a generous dusting of Parmesan