Step 1: In a medium bowl, combine the thawed and patted-dry shrimp with 2 tablespoons of olive oil, minced garlic, lemon zest, red pepper flakes (if using), 1/2 teaspoon of salt, and 1/4 teaspoon of black pepper. Toss gently to ensure the shrimp are evenly coated. Let this marinate for about 10-15 minutes at room temperature.
Step 2: While the shrimp are marinating, prepare the asparagus. Wash the spears and snap off the tough, woody ends. In a separate bowl, toss the asparagus with the remaining 1 tablespoon of olive oil, a pinch of salt, and pepper.
Step 3: Heat a large skillet or non-stick pan over medium-high heat. Once hot, add the seasoned asparagus. Sauté for 5-7 minutes, stirring occasionally, until the asparagus is tender-crisp and bright green. Remove the asparagus from the skillet and set aside.
Step 4: Add the marinated shrimp to the same hot skillet in a single layer. Cook for 2-3 minutes per side, or until the shrimp turn opaque pink and curl into a ‘C’ shape. Be careful not to overcrowd the pan; cook in batches if necessary to ensure even cooking. Overcooked shrimp can be tough, so watch them closely!
Step 5: Once the shrimp are cooked through, return the asparagus to the skillet with the shrimp. Squeeze fresh lemon juice over everything. Toss gently for about 30 seconds to combine and warm through.
Step 6: Remove from heat and transfer immediately to serving plates. Garnish with fresh chopped parsley or cilantro, if desired. Serve hot and enjoy!