Heat olive oil and butter in a large skillet or sauté pan over medium-high heat until butter is melted.
Add sausage and cook, breaking up as you go, until cooked through, 3-5 minutes.
Add shallot and garlic, and cook until softened and garlic is lightly browned, 2-3 minutes.
Add red pepper flakes, dried oregano, salt and pepper. Stir to combine and cook 1 minute.
Add tomato paste, reduce heat to medium and stir to combine. Cook 2-3 minutes, until deepened in color.
Add chicken broth and pasta, stir, and bring to a boil over high heat.
Once boiling, reduce heat to medium-low and simmer, stirring occasionally, for 10 minutes until most liquid is reduced. Be sure to stir occasionally to keep pasta from sticking.
Stir in heavy cream and basil, and bring heat to medium. Cook 10-12 minutes more, covered with a lid (stirring occasionally to prevent sticking), until pasta is cooked through and sauce is thick and creamy.
Turn off heat, and stir in Pecorino and Parmesan cheeses until fully combined.
Serve with additional basil.