Heat olive oil in a large skillet over medium heat.
Add onion and cook until translucent (~3-4 minutes).
Stir in garlic and cook for 30 seconds until fragrant.
Add tomato paste and cook for 1-2 minutes, stirring constantly.
Pour in vodka, stir, and simmer for 3-4 minutes to cook off the alcohol.
Add crushed tomatoes, red pepper flakes, salt, and pepper.
Reduce heat to low and simmer for 10 minutes, stirring occasionally.
Stir in heavy cream and Parmesan cheese until smooth.
Simmer for another 2-3 minutes.
Fold in fresh basil and adjust seasoning if needed.
For a smoother sauce, blend with an immersion blender or transfer to a countertop blender.
Toss with cooked pasta (e.g., penne, rigatoni) and garnish with extra Parmesan and basil.
