In a large pan begin by melting the butter and oil together.
Add the onions and red pepper and let that cook until just softened.
Add in the garlic and let cook another minute or two. Pour in the wine and let that cook until it reduces slightly.
In the mean time cook the pasta according to the directions. Once ready drain and set aside until you're ready to add it.
Back in the veggie pan add in the shrimp, red pepper flakes and lightly salt + pepper everything.
Once everything is warmed through but there is still plenty of liquid in the pan add in the cooked pasta and Parmesan. Toss so everything gets lightly coated in the cheese.
Taste and add salt + pepper if needed. Squeeze on some fresh lemon juice and sprinkle on the parsley.
Notes
I like to use cooked shrimp because once thawed it's really fast to have it ready to eat.