Bring a large pot of generously salted water to a rolling boil. Cook the noodles according to package instructions until al dente.

Before draining the noodles, carefully ladle out at least 120 ml of the hot, starchy noodle water and set it aside.

While the noodles cook, melt 15 ml of butter in a large skillet over medium heat. Add the minced garlic and scallion whites, gently cooking until aromatic, about 1 minute.

Whisk the gochujang paste, soy sauce, and honey into the skillet, stirring continuously for 1 minute until the chili paste loosens and slightly caramelizes.

Add the remaining 30 ml of butter and 60 ml of the reserved noodle water to the skillet, swirling vigorously until a glossy, emulsified sauce forms.

Transfer the drained noodles directly into the pan. Toss and stir continuously over low heat for 1 to 2 minutes until every strand is thoroughly coated in the spicy butter glaze.

Remove from heat, drizzle with sesame oil, and divide between two serving bowls. Garnish generously with sliced scallion greens and toasted sesame seeds.