Heat one tablespoon of butter in a large skillet over medium-high heat. Season the seafood with half the kosher salt and black pepper.
When the butter starts foaming, add the seafood to the skillet and cook, stirring often, until just cooked through and no longer translucent, about 3 minutes.
Using a slotted spoon, transfer the seafood to a plate, cover it with foil, and set aside.
Pour the liquids out of the skillet, wipe it clean with paper towels (careful, it’s hot), and add the remaining butter. Reduce the heat to medium.
When the butter starts foaming, add the garlic to the skillet. Sauté, stirring, until fragrant, 30-60 seconds, depending on how hot your skillet is.
Reduce the heat to medium-low. Add the cream, cayenne pepper, and the remaining kosher salt and black pepper. Bring the sauce to a gentle simmer, stirring. This should take about 1 minute.
Add the parmesan cheese and gently stir until melted, about 30 seconds.
Add the seafood back to the skillet. Gently stir to combine with the sauce and reheat, about 1 more minute.
Transfer the skillet contents, including the sauce, to a serving plate, sprinkle the dish with parsley, and serve.
Video
Notes
While you can theoretically cook the seafood from frozen (though it will take longer and won't cook as evenly), I prefer to thaw it first, either overnight in the fridge or by submerging it in a bowl of cool water for 5 minutes, replacing the water once, and then drying the pieces on paper towels.
Please use freshly minced garlic cloves. The garlic is very important here, and jarred minced garlic won't be the same.
You can keep the leftovers in a sealed container in the fridge for up to 3 days. Reheat them gently, though. It's best to use the microwave at 50% power and reheat them covered.
You can freeze the cooled leftovers in a freezer-safe container for up to three months. Thaw them overnight in the fridge and reheat covered in the microwave.