Add 1 ½ t olive oil to a large sauté pan over medium-high heat and swirl to coat the bottom of the pan. Add sausage to the pan and brown while breaking up meat with a spoon. When browned, remove sausage from pan. Add 1 T oil to the same sauté pan and swirl to coat. Add the chopped onion and sauté for 3 minutes, stirring occasionally. Then add sliced mushrooms and sauté 4 more minutes, stirring occasionally. Add garlic and sauté an additional minute, stirring constantly to combine. Stir in sausage, 1/8 t of salt and can of tomatoes. Bring to a simmer and reduce heat. Simmer for 15 minutes. White tomato mixture is simmering, pour broth and water into a medium saucepan and bring it to a boil. Once boiling, add polenta and stir well. Reduce the heat and simmer 20 minutes or until thick (mine was thick in a little less time), stirring occasionally. Once polenta is thick, stir in cream cheese, butter and 1/8 t of salt until thoroughly combined. Serve 2/3 c ragu over 2/3 c polenta.