Scallion Oil Bucatini with Runny Eggs

Bring 4 quarts water and 1 tablespoon salt to a boil in a large pot. Add pasta; cook for 2 minutes less than the low end of the package instructions.

Meanwhile, line a plate with a double layer of paper towels. Thinly slice 3 scallions and set aside. Cut the remaining 3 scallions into 3-inch segments, then thinly slice them lengthwise to create 3-inch matchsticks. Combine the scallion matchsticks and oil in a large skillet over medium heat. Cook, stirring occasionally, until the scallions are browned, reducing the heat if they begin to darken too quickly, 5 to 7 minutes. Remove from heat; transfer the scallions to the prepared plate with a slotted spoon or tongs. Transfer 1½ teaspoons of the oil to a small bowl, leaving the remainder in the pan.

Place the skillet with the scallion oil over medium-low heat. Reserve 1½ tablespoons sliced scallions for garnish, then add the remainder to the pan along with garlic. Cook, stirring often, until the mixture is fragrant and the garlic is just beginning to color, 1 to 3 minutes. Add crushed red pepper, if using, and cook, stirring, for 1 minute; remove from the heat until the pasta is done.

When the pasta is done, place the skillet over high heat and use tongs to transfer the cooked pasta to the pan. Add 1/3 cup of the pasta cooking water, lemon zest, lemon juice, soy sauce, butter and pepper; toss, adding more pasta water as needed, until the pasta is tender and the sauce just clings to the pasta but still pools slightly in the bottom of the pan, 3 to 5 minutes. (We used about 1/2 cup additional pasta cooking water during our test.) Divide the pasta among 4 shallow bowls or plates.

Heat the reserved scallion oil in a large nonstick skillet over medium-high heat until shimmering. Working quickly, crack eggs into the pan and sprinkle with the remaining pinch of salt; cover and cook for 1 minute, then uncover and continue to cook to desired doneness (about 1 minute for sunny-side up, or flip and continue to cook for over easy, medium or hard).

Top each portion of pasta with an egg. Sprinkle with the fried scallions and reserved sliced scallions, and with Parmesan and cracked pepper, if desired.