Time 65 minutes

Serving 4

• 3 tablespoons (45g) unsalted butter
• 1 medium (8-ounce; 225g) yellow onion, diced
• 3 medium cloves garlic, thinly sliced
• Pinch red pepper flakes
• Kosher salt
• One 4 ½-ounce (130g) tube concentrated tomato paste or 6-ounce (170g) can tomato paste
• One 14 ½-ounce (411g) can whole peeled tomatoes
• 1 cup (240ml) heavy cream
• 1 pound (450g) short tubular pasta, such as rigatoni or penne
• ¼ cup (60ml) vodka, plus more if desired
• 2 ounces (55g) grated Parmigiano-Reggiano, plus more for serving

Step 1
In a large (3- or 4-quart) saucepan or small Dutch oven, melt butter over medium heat. Add onions, garlic, and red pepper flakes, season lightly with salt, and cook, stirring frequently, until onions are very soft but not browned, about 15 minutes; lower heat if needed to prevent browning.

Step 2
Add tomato paste and cook, stirring, until tomato paste is fragrant and thick, about 3 minutes. Stir in canned tomatoes with their liquid. Bring to a simmer, then cook, stirring often and crushing the whole tomatoes roughly with a spoon, until sauce has thickened slightly, about 10 minutes.

Step 3
Add cream, and stir to incorporate. Transfer sauce to a blender, and blend until very smooth (you may be able to make an immersion blender work, but in our tests the sauce level was too low to safely avoid splattering). Wipe out pot, then return blended sauce to it. Season lightly with salt.

Step 4
Add cream, and stir to incorporate. Transfer sauce to a blender, and blend until very smooth (you may be able to make an immersion blender work, but in our tests the sauce level was too low to safely avoid splattering). Wipe out pot, then return blended sauce to it. Season lightly with salt.

Step 5
Using a spider skimmer or slotted spoon, transfer pasta directly to sauce pot along with ½ cup (120ml) pasta water (alternatively, reserve 2 cups pasta water, then drain pasta in a colander, then add to sauce with ½ cup of the reserved water). Increase heat to high, and cook, stirring constantly, until pasta is well coated in sauce and reaches the al dente stage, about 3 minutes. If sauce thickens too much before pasta is ready, add more pasta water in ¼ cup (60ml) increments as needed.