Bring a large pot of salted water to a rolling boil, then add the fettuccine and cook until just al dente, about 8 minutes. Reserve a cup of pasta water, then drain and set aside.
While the pasta cooks, pat the shrimp dry and season lightly with salt and pepper. Heat a large skillet over medium heat and add the butter. Once melted and bubbling, add the shrimp in an even layer.
Cook the shrimp for about 2-3 minutes per side, until they turn pink, opaque, and develop a slight golden sear. Remove the shrimp from the skillet and set aside.
In the same skillet, add the minced garlic and sauté for about 30 seconds until fragrant and golden, being careful not to burn it.
Pour in the heavy cream, stirring gently to loosen any browned bits from the bottom of the pan. Bring it to a gentle simmer and cook for 2-3 minutes until slightly thickened and creamy.
Gradually add the grated Parmesan cheese, stirring constantly until melted and the sauce is smooth. If the sauce is too thick, loosen it with a splash of reserved pasta water.
Return the cooked shrimp to the skillet, squeeze in the lemon juice, and stir to combine. Check the seasoning and add salt and pepper as needed.
Add the drained pasta to the skillet, tossing gently to coat every strand with the creamy sauce. Warm through for about 1-2 minutes, adding more pasta water if necessary to loosen the sauce.
Remove from heat and let rest for a minute. Serve immediately, garnished with extra Parmesan or herbs if desired, enjoying the silky texture and fragrant aroma.
