Heat a large skillet over medium-high heat. Add the unsalted butter and allow it to melt and bubble, being careful not to let it burn.
Once the butter is melted, add the minced garlic and red pepper flakes. Sauté for about 30 seconds to 1 minute until the garlic becomes fragrant but not browned.
Add the shrimp to the skillet in a single layer. Season with salt and pepper to taste. Cook the shrimp for about 2-3 minutes on one side until they turn pink and slightly opaque.
Flip the shrimp and cook for another 1-2 minutes on the other side. Ensure they are cooked through and the internal temperature reaches 120°F (49°C).
Remove the skillet from heat, then squeeze the fresh lemon juice over the shrimp and toss to coat evenly. Add the chopped parsley for a fresh flavor lift and stir to combine.
Serve immediately over cooked rice or pasta, ensuring to drizzle some of the buttery sauce over the top. Garnish with lemon slices.
Notes
Adjust red pepper flakes to taste for desired spiciness.