Garlic Butter Shrimp Scampi

Bring a large pot of well-salted water to a boil and cook the pasta according to package directions until al dente.
Before draining, scoop out 1 cup of the starchy pasta water and set it aside, then drain the pasta.
Pat the shrimp completely dry with paper towels and season with the salt and pepper.
Heat the olive oil and 2 tablespoons of the butter in a large skillet over medium-high heat until the butter melts and sizzles.
Add the shrimp in a single layer without crowding the pan and cook for 1 to 2 minutes per side until they turn pink and curl into a loose C shape; remove them to a plate immediately so they do not overcook.
Lower the heat to medium, add the garlic and red pepper flakes to the same pan, and cook for 30 seconds until fragrant, not browned.
Pour in the white wine and simmer for 2 minutes to cook off the raw alcohol smell.
Add the chicken broth and lemon juice and simmer for 3 minutes until the sauce reduces slightly.
Stir in the remaining 2 tablespoons of butter until it melts into a glossy sauce.
Return the shrimp to the pan along with the cooked pasta and toss well, adding splashes of the reserved pasta water as needed to loosen the sauce so it coats every strand.
Check that the shrimp are opaque all the way through and tightly curled; if any look translucent in the center, toss for another 30 seconds over low heat.
Stir in the parsley, taste and adjust salt, then serve immediately in warm bowls.
Avoid leaving the shrimp in the hot pan while you finish the sauce, since carryover heat will turn them rubbery.