Boil water, salt it like you mean it, and cook pasta until al dente. Reserve a cup of the starchy water.
In a large skillet, heat olive oil over medium heat. Sauté onion (if using) until translucent, about 3–4 minutes. Add garlic and cook another 30 seconds until fragrant.
Add red pepper flakes and stir. If you love heat, go a pinch more. Don’t burn the garlic—we’re going for sexy aroma, not charred misery.
Pour in vodka. Let it simmer for 2–3 minutes to cook off the raw edge. The kitchen should smell like spicy kitchen-sunrise, not a chemistry experiment.
Stir in crushed tomatoes and simmer 5 minutes. If the sauce looks too thick, splash in some pasta water.
Lower heat and swirl in cream. Season with salt and pepper. Simmer 2–3 minutes until glossy and rich.
Toss the drained pasta into the sauce, adding a bit of pasta water if needed to loosen. Coat every noodle, then turn off the heat.
Finish with chopped herbs and cheese if you’re feeling fancy. Serve hot and smile while the peppery-silty fragrance fills the room.