Bring a large pot of salted water to a boil and cook penne according to package directions until al dente.
Reserve 1/4 cup of pasta water before draining the pasta.
In a large skillet over medium heat, melt the butter with the olive oil.
Add the diced onion and sauté until translucent, approximately 5 minutes.
Stir in the minced garlic and red pepper flakes, cooking for 1 minute until fragrant.
Add the tomato paste and cook, stirring constantly for 3 to 5 minutes until the paste darkens to a deep brick red.
Pour in the vodka and stir to deglaze the pan; simmer for 2 to 3 minutes until the liquid is reduced by half.
Stir in the heavy cream and bring to a gentle simmer until the sauce thickens slightly.
Add the cooked pasta and grated Parmesan cheese to the skillet, tossing to coat thoroughly.
Adjust consistency with reserved pasta water if necessary, season with salt and pepper, and garnish with fresh basil before serving.