Bring a large pot of boiling water to boil, then add 2 tablespoons of kosher salt.
Dump in a 16-ounce box of dried capellini, and allow the noodles to cook until they’re tender but give just a hint of resistance when you take a taste test.
While the pasta cooks, heat a large skillet and add 1 to 2 sticks of unsalted butter, depending on how rich you’d like your sauce to taste.
Once the butter is melted, stir in the zest and juice of the 2 lemons.
Season with 2 teaspoons of kosher salt and 1 teaspoon black pepper. Gently swirl the pan to mix.
When the pasta is cooked, there’s no need to drain it. Simply reach for a pair of tongs and lift the pasta out of the water, then transfer it to the sauce and toss to combine.
Cook for 1 more minute, ladling in as much pasta water as you like to moisten the pasta and reach your preferred consistency.
Garnish with additional lemon zest, salt, and pepper, finish with a squeeze of lemon, and enjoy ASAP.
