In a large pot, warm the olive oil and butter over medium heat until butter is melted.

Add the onion and saute until softened and beginning to turn translucent, typically about 3-5 minutes.

Add the garlic to the pan and cook, stirring, until fragrant (about 30 seconds).

Add tomato paste, Italian seasoning, salt, black pepper and red pepper flakes, stirring until everything is well combined. Continue to cook, stirring, until tomato paste deepens in color.

Gradually pour in the vodka, scraping the bottom of the pan as you do to scrape up any browned bits. Cook, stirring frequently, until vodka reduces by half and loses its potent alcohol scent.

Add tomatoes and basil, breaking/mashing them up with your spatula as you cook.

Stir in the cream.

Puree. If you have an immersion blender, use it to puree the sauce until completely smooth. Otherwise, transfer the sauce in batches to a blender to process until smooth, then return to the pot.

Reduce heat to low and bring the sauce to a simmer. Allow it to cook, uncovered, for about 30 minutes, stirring occasionally. If serving with pasta, this is a good time to begin preparing it according to package instructions. You can serve sauce over cooked pasta or toss the two together before serving. See note for serving with pasta.

After simmering, add parmesan cheese and stir in until melted. Use as desired or store in the refrigerator in an airtight container for up to a week before using.