Penne alla vodka was my mom's favorite pasta for special celebrations, but it's simple enough to make with any pasta shape for a weeknight dinner. This creamy, rich version comes together in under 30 minutes.
Bring a large pot of salted water to a boil and cook the pasta according to the package directions until al dente. Drain.
While the pasta is cooking, combine 2 tablespoons of the oil, the garlic, shallots or onions and crushed red pepper in a large skillet and cook over medium-high heat, stirring occasionally, until everything starts to sizzle and begins to soften, 1 to 2 minutes. Stirring constantly, carefully pour in the tomato sauce (it will sizzle) until well combined with the other ingredients. Remove from the heat and add the vodka, 1/2 teaspoon salt and a few grinds of black pepper. Return to the heat and bring to a simmer and cook, stirring occasionally, until the sauce has thickened and reduced slightly, about 5 minutes. Stir in the cream and continue to cook for 1 minute.
Add the pasta to the skillet and stir to coat well. Let the pasta cook briefly in the sauce until it thickens a little more and clings nicely to the pasta. Stir in the Parmesan, remaining 1 tablespoon oil, 1/4 teaspoon salt and a few grinds of black pepper. Transfer the pasta to a serving dish and sprinkle with the parsley if using. Serve, passing more Parmesan at the table.