Cook the pasta. Bring a large pot of water to a boil. Add the teaspoon of salt to the boiling water, followed by the rigatoni. Cook the pasta according to the package instructions until al dente. Once cooked, drain the pasta, reserving about 1 cup of the pasta water. Set aside.
Saute the aromatics. In a large skillet or saucepan, heat the olive oil over medium heat. Add the shallots and saute until translucent. Add the garlic and sauté for 15 seconds or until fragrant.
Build flavor. Stir in the tomato paste, butter, and red pepper flakes. Saute for 2-3 minutes until the tomato paste has darkened in color.
Deglaze. Pour the vodka into the skillet and cook for 2-3 minutes, stirring occasionally to knock any brown bits off of the bottom of the pan.
Make it creamy. Whisk in the heavy cream and let the sauce simmer for a few minutes.
Make it cheesy. Turn the heat to low and add the cheese. Stir until melted.
Put it all together. Add the cooked rigatoni to the skillet. Toss to coat the pasta. If the sauce is too thick, stir in a bit of the reserved pasta water to thin it out. Turn off the heat and season with salt and pepper to taste.