Set a large pot of water over high heat and bring it to a full boil. Fill a medium bowl with cold water and a handful of ice if you have it.

Lower the eggs into the boiling water with a spoon so they do not crack. Cook them for 7 minutes for firm whites and jammy yolks.

Lift the eggs out of the pot and put them in the bowl of cold water. Let them cool while you cook the pasta.

Add a generous spoonful of salt to the same pot of water and bring it back to a boil.

Add the spaghetti to the boiling water. Stir for the first 30 seconds so the strands do not stick together.

Cook the spaghetti until it is tender but still has a little bite, using the package time as a guide. Keep the pot uncovered so the water does not boil over.

While the spaghetti cooks, put a large skillet over medium heat and melt 2 tablespoons of the butter.

Add the scallion whites and garlic to the skillet. Cook for about 1 minute, stirring often, until the scallions soften and the garlic smells fragrant but is not brown.

Add the chopped kimchi and its reserved juice to the skillet. Cook for 2 to 3 minutes, stirring, until the butter turns orange and the kimchi looks a little darker at the edges.

Add the remaining 2 tablespoons butter to the skillet and let it melt into the kimchi. Turn the heat to low so the sauce stays warm.

When the spaghetti is ready, scoop 1 cup of the pasta cooking water into a mug or measuring cup. Drain the spaghetti in a colander right away.

Transfer the drained spaghetti to the skillet. Toss it with the kimchi butter for about 30 seconds so the noodles are well coated.