In a large bowl, combine the shrimp, 2 tbsp olive oil, minced garlic (4 cloves), dried oregano, red pepper flakes (if using), juice from 1/2 lemon, lemon zest, salt, and black pepper. Toss well to coat. Let marinate for at least 10 minutes while you prepare the orzo, or up to 30 minutes in the refrigerator.

Heat 1 tbsp olive oil in a large skillet (with a lid) over medium heat. Add the finely diced shallot and cook for 2-3 minutes until softened and translucent.

Add the minced garlic (2 cloves) and cook for another minute until fragrant, being careful not to burn it.

Stir in the uncooked orzo pasta, toasting it gently for 1-2 minutes until lightly golden.

Pour in the dry white wine (if using) and stir, allowing it to cook off for 1 minute until mostly absorbed.

Add the chicken broth, salt, and pepper. Bring to a simmer, then reduce heat to low, cover, and cook for 10-12 minutes, or until the orzo is al dente and most of the liquid has been absorbed. Stir occasionally to prevent sticking.

Once cooked, remove the lid. Stir in the remaining 1/2 lemon juice, 1/4 cup grated Parmesan cheese, and 2 tbsp unsalted butter. Taste and adjust seasoning as needed. Keep warm and covered.

While the orzo finishes cooking, heat a separate large skillet (or clean out the orzo skillet if you prefer, but a second pan makes it quicker) over medium-high heat. Add the marinated shrimp in a single layer, making sure not to overcrowd the pan. Cook for 1-2 minutes per side, or until pink and opaque. Do not overcook, as shrimp cooks very quickly.

Once the shrimp are cooked, add them directly to the skillet with the orzo. Gently toss to combine.

Garnish generously with fresh chopped parsley and extra grated Parmesan cheese, if desired. Serve immediately.