Step 1

Heat 2 Tbsp. butter in a large skillet over medium-high. Add chopped kimchi and gochujang and cook, stirring occasionally, until kimchi is softened and lightly caramelized, about 4 minutes. Add broth and kimchi juice and bring to a simmer. Cook until liquid is slightly reduced, about 3 minutes.

Step 2

Meanwhile, boil noodles according to package directions.

Step 3

Using tongs, transfer noodles to skillet and add remaining 3 Tbsp. butter; cook, tossing often, until sauce coats noodles, about 2 minutes. Season with salt if needed. Divide among bowls and top with egg yolks, scallions, and sesame seeds.