Bring a large pot of salted water to a boil, then cook 400 g linguine until al dente according to package directions. Before draining, reserve 120 ml pasta cooking water (reserved), then set pasta aside.

Pat 500 g large shrimp, peeled and deveined dry and season with salt, pepper, and 0.5 tsp red pepper flakes. Heat 2 tbsp olive oil in a large skillet over high heat, then cook shrimp in a single layer for 1–2 minutes per side until pink and just cooked through, and remove to a plate.

Reduce heat to medium and melt half of 80 g unsalted butter in the same pan. Sauté 5 minced garlic cloves for 1 minute until fragrant but not browned.

Pour in 120 ml dry white wine and let it reduce by half, about 3 minutes. Stir in the lemon juice and zest from 3 lemons, then cook 30 seconds to combine.

Add the drained pasta to the pan and toss well. Add 120 ml pasta cooking water (reserved) a splash at a time to loosen the sauce, then add the remaining 80 g unsalted butter and toss until the sauce is glossy and clings to the noodles.

Return the shrimp to the pan and toss gently to warm through. Finish by tossing in 3 tbsp chopped fresh parsley and 40 g Parmesan (optional), then taste and adjust salt and pepper before serving immediately.