Heat oil and butter in a large pot over medium heat until butter is melted and pan is hot. Add onion and cook, stirring, until softened (about 3-5 minutes). Add garlic and cook until fragrant.
Add vodka and cook, scraping the bottom of the pot, until vodka is reduced by about half and you no longer get slapped in the face by the smell of alcohol if you whiff the steam.
Add tomato paste, Italian seasoning, salt, pepper, and red pepper flakes and cook, stirring, until mixture is smooth and tomato paste is well incorporated.
Reduce heat and simmer for at least 30 minutes, stirring occasionally. Prepare pasta while mixture simmers. When finished cooking, reserve 1 cup of pasta water before draining.
Add cooked, drained pasta to pot with a splash of reserved pasta water and add grated parmesan and sliced basil. Stir well and continue to simmer over low heat. Serve and Enjoy!