Soak the fresh clams in cool water for 30 minutes to an hour to allow the clams to spit out any sand inside. Remove each clam from the water and scrub the outside to remove any remaining particles. This can be done the day before.
Cook the linguine in a pot of heavily salted water (at least 1 tablespoon) for about 2 minutes less than package instructions. Drain but don't rinse. Reserve some of the pasta water.
Melt the butter in a skillet over medium-low heat and add garlic and shallots. Cook for 3-5 minutes until they soften and the flavors start to bloom.
Add the wine and parsley and simmer until reduced, about 5-7 minutes.
Add 2 tbsp. of the reserved clam liquid, the clam meat and the fresh clams. Cover and cook for about 5-10 minutes, or until fresh clams open. Add the salt and pepper. (add additional salt to taste if necessary)
Garnish with a squeeze of fresh lemon and parsley and serve.
Make sure to add plenty of salt (at least 1 tablespoon) to the pasta water. This is what adds flavor to the pasta.
Discard any unopened clams after you have cooked them.
Save some of the pasta water to help thicken up the sauce if necessary. If the sauce is watery add 1-2 tablespoons of pasta water. The starch should help to thicken it.
If your pasta sauce is still runny, add 2 teaspoons of cornstarch to 1 tablespoon of water and mix to combine. Slowly add the cornstarch slurry to the pasta, just a touch at a time, until the desired thickness is reached. Personally, I have not needed to do this.
Add additional salt and pepper to taste after mixing the linguine in with the sauce.