1. Thoroughly clean the clams in several changes of water, then drain them in a colander.
2. Peel and chop the garlic cloves. Wash and chop the parsley. In a saucepan, melt the garlic over low heat with the olive oil for 3 minutes. Add the clams, white wine, and half of the parsley, season with pepper. Cover the pot and cook for 8 to 10 minutes over high heat, stirring the clams halfway through cooking.
3. Turn off the heat. Strain 40 cl of the clam cooking juice and pour it into a saucepan. Bring to a boil over medium heat to reduce it by about one-third.
4. Meanwhile, drain the clams. Reserve a quarter of them with their shells and shell the rest.
5. Cook the linguine in a large pot of salted boiling water according to the package instructions.
6. Incorporate the butter in small pieces into the saucepan with the reduced clam cooking juice, whisking constantly. Check the seasoning with salt and pepper, then add the remaining parsley. Blend everything for 10 seconds with an immersion blender to obtain a smooth sauce.
7. Drain the pasta and toss it in a bowl with the shelled clams and the hot sauce.
8. Divide the preparation among the plates. Add a few clams with their shells on top and serve with grated Parmesan cheese.