This extra ingredient makes a huge difference.
You might not know it, but pasta water is an incredible resource.
Combining pasta and boiling water doesn’t just transform dry pasta to tender-yet-toothy noodles. That water itself changes as well by taking on some of the pasta’s starch, and overlooking pasta water’s potential is a big mistake. Even if you do regularly utilize your pasta water to create luscious sauces, it’s possible you’re still overlooking a crucial ingredient: salt.
Robby Melvin, a recipe developer in our test kitchen, explains why:
Once your water is really boiling (not just making a few bubbles!) add 3 tablespoons of salt per 8 ounces of water to achieve perfect salinity. You don’t have to be fancy: Kosher salt will get the job done, and there’s no need for any oil. As long as you’re stirring whatever’s in the pot, you need not worry about your noodles sticking.
When the pasta’s done boiling, reserve a cup of pasta water before draining your pot. You don’t have to use all of it, but that spare pasta water will upgrade even the simplest homemade sauce. Take Robby’s sauce, for example: He combined butter and a few splashes of pasta water to make a base that’s smooth, starchy, and most importantly, well salted. After reaching his desired consistency, he melted shaved Parmesan on top of the warm pasta to bulk up his sauce before finishing with chopped parsley.