Pat the shrimp dry with paper towels and season lightly with salt and pepper.
Heat olive oil and 1 tablespoon butter in a large skillet over medium-high heat. Add shrimp and cook for 2-3 minutes per side until pink and opaque. Remove shrimp and set aside.
In the same skillet, add remaining butter and sauté garlic and red pepper flakes (if using) for about 30 seconds until fragrant.
Pour in chicken broth and scrape up any browned bits from the bottom of the pan. Let it simmer for 1 minute.
Reduce heat to low and stir in heavy cream and Parmesan cheese until the sauce is smooth and slightly thickened.
Return shrimp to the skillet and toss gently to coat in the sauce. Cook for another 1-2 minutes.
Remove from heat and stir in lemon juice and parsley. Adjust seasoning if needed.
Notes
Serve immediately over cooked pasta or rice for a complete meal.