Pat the shrimp dry with paper towels and season lightly with salt and pepper.
Melt 2 tablespoons of butter in a large skillet over medium-high heat.
Add the shrimp to the hot skillet in a single layer. Cook for 1 to 2 minutes per side until pink and opaque. Do not overcrowd the pan; cook in batches if necessary. Remove the cooked shrimp and set aside.
Reduce the heat to medium. Add the remaining 2 tablespoons of butter and the minced garlic to the skillet. Cook for about 30 seconds until fragrant, being careful not to burn the garlic.
Pour in the white wine or broth, scraping up any browned bits from the bottom of the pan. Let it simmer for 1 minute.
Stir in the lemon juice, lemon zest, and red pepper flakes, if using. Cook for 30 seconds until the sauce slightly thickens.
Return the cooked shrimp to the skillet. Toss gently to coat the shrimp in the sauce.
Remove the skillet from the heat. Stir in the chopped fresh parsley. Taste and adjust seasoning with more salt or pepper if needed.
Serve immediately.
Notes
Serve this shrimp over pasta, rice, or with crusty bread to soak up the extra garlic butter sauce.
For best results, use fresh lemon juice rather than bottled.
Do not overcook the shrimp; they cook very fast once added to the hot pan.