Roast your tomatoes first. Toss halved tomatoes with the garlic, 1-2 tbsp of olive oil and S&P. Roast on wax paper on cookie sheet for about 20-25 minutes. Once done set aside.
Heat 1-2 tbsp of olive oil in a large skillet. Cook onions till they are translucent. Add the garlic & stir for another minute. Transfer to a bowl.
In the same pan, head another tbsp of olive oil over high heat and sear the mushrooms adding a pinch of salt. When they are browned a little bit de-glaze the pan with the red wine. Cook on high for two minutes.
Add the lemon juice, and stir in for a minute. Then add the onion & garlic mix. Saute for another minute. Add the heavy cream and 1 tsp of black pepper. Finally add the tomatoes. Heat over medium until the sauce is thick & creamy. Simmer on low till pasta is ready. If it gets a little thick add a little water.
Pour sauce over cooked pasta and then add your Parmesan .