Heat 1 tablespoon olive oil in a large skillet over medium heat. Add the chicken pieces, season with salt and pepper, and cook for 5-7 minutes, until golden brown on all sides and cooked through. Remove the chicken from the skillet and set aside.

Bring a large pot of salted water to a boil. Cook the pasta according to package instructions until al dente, about 8-10 minutes. Drain and reserve 1 cup of pasta water for later. Set the pasta aside.

In the same skillet, add the remaining 1 tablespoon olive oil. Sauté the onion and garlic over medium heat until soft and fragrant, about 3 minutes. Stir in tomato paste and cook for 2 minutes.

Add the vodka and let it simmer for about 3 minutes, allowing the alcohol to cook off.

Stir in crushed tomatoes and simmer for 5-7 minutes, allowing the flavors to meld.

Reduce the heat to low and stir in the heavy cream. Let it simmer for 3-5 minutes, thickening the sauce. Add Parmesan cheese and stir until the sauce is creamy and smooth. Taste and adjust seasoning with salt, pepper, and red pepper flakes (optional).

Add the cooked pasta to the skillet, tossing to coat evenly in the sauce. Add the cooked chicken back to the skillet, mixing well until everything is combined.

Serve the Vodka Sauce Pasta with Chicken on plates or in a large serving dish. Garnish with fresh basil and additional Parmesan cheese. Optionally, drizzle olive oil or squeeze lemon juice for extra flavor.