Bring a large pot of salted water to a boil over high heat.
Place a large non-stick pan over medium heat and add the diced pancetta, sauteing it until golden brown.
Once all of the pancetta is browned, add the vodka to the pan and cook it until it reduces by half, about 3 minutes.
Add the prepared marinara sauce to the pan, then whisk in the heavy cream. Reduce the heat to low and let the sauce simmer for 10 minutes.
While the sauce is simmering, add the pasta to the boiling water and cook it until al dente.
Drain the cooked pasta and add it to the pan with the sauce, tossing to coat.
Serve the pasta topped with Parmesan cheese.
If you don't have a non-stick pan, add 2 tablespoons of unsalted butter to a regular pan, then add the diced pancetta and continue the method of preparation above.
As the age-old rule stands, never cook with alcohol (or wine) that you wouldn't drink. Although it's tempting to skimp on the vodka and opt for a cheap brand, I encourage you to splurge on the higher-end varieties, as it really does impact the flavor of the sauce.
Ask the butcher at your local supermarket about purchasing a thick slice of pancetta. But if one thick slice isn't an option, you can use the pre-packaged thin slices that are widely available.