Heat the oven: Preheat to 425°F (220°C). Grease a 9x13-inch baking dish or similar casserole.
Cook the pasta: Bring a large pot of salted water to a boil. Cook pasta to al dente, 1–2 minutes less than package directions.
Reserve 1/2 cup pasta water, then drain.
Sauté the aromatics: In a large skillet, warm 2 tablespoons butter and 2 tablespoons olive oil over medium heat. Add garlic and red pepper flakes. Cook 30–60 seconds, just until fragrant.
Don’t brown the garlic.
Deglaze and build the sauce: Pour in white wine. Simmer 2–3 minutes to reduce slightly. Stir in remaining 2 tablespoons butter, lemon zest, and 2 tablespoons lemon juice.
Season with salt and pepper.
Cook the shrimp: Add shrimp in an even layer. Cook 1–2 minutes per side until just pink and slightly curled. Don’t overcook; they’ll finish in the oven.
Add greens or tomatoes (optional): Toss in spinach to wilt or cherry tomatoes to warm through, about 1 minute.
Toss with pasta: Add drained pasta and parsley to the skillet.
Toss to coat, adding a splash of reserved pasta water if it looks dry. Adjust lemon, salt, and pepper to taste.
Assemble the bake: Transfer pasta mixture to the baking dish. Top with mozzarella and Parmesan.
Sprinkle breadcrumbs evenly over the top.
Bake: Bake 6–8 minutes until cheese melts. Broil 1–2 minutes at the end for a golden top, watching closely.
Finish and serve: Let rest 2–3 minutes. Garnish with extra parsley and a squeeze of lemon.
Serve hot.