On medium-high heat, bring a medium sauce pot of water to a boil, add pasta and cook until al denta. Reserve 1/2 cup of pasta water. Drain pasta and set aside.
Heat oil in a skillet over medium to high heat, add shrimp and pan sear for about 3 minutes on each side. Transfer to a plate.
Add in garlic and cook for about 30-40 seconds until fragrant. Add the crushed tomatoes, marinara sauce, red pepper flakes and salt, simmer for 10 minutes.
Stir in vodka and cook for another 3-4 minutes.
Stir in the cream and return shrimp to the skillet and simmer for another 5 minutes.
Season with salt and pepper, add the remaining parsley. If desired, add Parmesan.
