Put a large pan of salted water on to boil for the pasta. Heat the olive oil and butter in a wide, shallow pan over fairly high heat.
Add the mince, break it up well, and brown hard on high heat so you develop a crust around the outside of the meat. Season with salt and pepper. Remove once done.
Finely dice the onion and garlic. Add both to the pan, cook hard, stirring constantly, until softened and starting to catch a little colour at the edges.
Finely chop the rosemary leaves, add to the pan, and cook briefly until fragrant.
Add the mince, break it up well, and brown hard on high heat without crowding the pan. Season with salt and pepper.
Add the wine and let it bubble off almost completely, scraping the base of the pan. The stock then follows.
Roughly chop the olives and capers, then stir them in.
Once this has cooked for 4-5mins & the wine and stock has reduced a little, take it off the heat and stir through the crème fraîche until it’s mixed in well.
Meanwhile, cook your pasta so it’s ready in time.
Toss the pasta through the sauce with a splash of pasta water to loosen.
Finely chop the parsley and scatter over, along with grated Parmesan and a final crack of black pepper.
