Heat a large skillet over medium high heat. Add butter to the skillet. 

When butter melts and stops foaming, add shrimp to the skillet. Be sure the shrimp do not touch. If skillet is too small, cook shrimp in batches. 

When the first side of the shrimp browns, turn shrimp over. When second side of shrimp is browned and shrimp is opaque, remove shrimp to a plate and set aside.

Turn heat to medium-low. Add garlic to the pan and cook, stirring constantly, for one minute. 

Add lemon juice to skillet. Cook, scraping up browned bits on the pan, until lemon juice is almost completely evaporated.

Pour cream into the skillet. Turn heat to medium and bring to a simmer while whisking frequently. Turn heat to low.

Stir in parmesan cheese. When cheese has melted and sauce has thickened, add the shrimp and any accumulated drippings. Turn off the heat.

Stir in the basil, red pepper flakes, and black pepper. Taste the sauce before adding the salt as the parmesan cheese adds a bit of saltiness as well. After salting, taste again and adjust seasoning if desired.