In a deep-sided skillet (with lid) heat oil and cook sausages over medium heat until browned on both sides and cooked all the way through. Cook with lid on to hold in heat.
Meanwhile puree tomatoes in a food processor, set aside.
Set sausages aside and drain all but 1 Tb drippings from pan. Sauté onions & garlic in drippings for a couple minutes, until tender.
Meanwhile carefully slice up sausages (1/4 - ½ inch thick.)
Start your pasta cooking.
When the onions are tender, add the wine, pureed tomatoes, rosemary, parsley, salt & pepper, and sausages.
Stir together and cook on medium low heat for 10 minutes.
Stir occasionally.
When the pasta is done, drain and place it in a large serving bowl.
Stir the mascarpone cheese into the sauce until it is melted and combined.
Pour the sauce over the pasta and gently toss to coat.
Serve with some grated Parmesan on top.
Enjoy!
Notes
Note: I use a beef Italian sausage now so that this is biblically clean.