Add remaining tablespoon of olive oil to a large skillet with the sliced onion. Cook until softened, about 2 - 3 minutes. Then add the garlic and continue to cook for 30 - 60 seconds, or until fragrant. Add the white wine and simmer until reduced by half. Lastly you'll add the tomatoes, oregano, half the parsley (reserve the remaining for garnish), salt, ½ cup of the pasta water, and red pepper flakes. Bring to a simmer and allow to thicken, stirring occasionally for 4 - 6 minutes.
Transfer the cooked pasta and shrimp to the sauce along with the butter, gently tossing to coat. Garnish with remaining parsley and enjoy!
Recipe by Slice of Jess at https://sliceofjess.com/smoky-shrimp-fra-diavolo-linguine-by-rachael-ray/