Start by bringing a large pot of water to a rolling boil over high heat. Add noodles and cook according to package directions (3-4 minutes). Drain and rinse under cold water; set aside.

In a medium bowl, combine gochujang, soy sauce, brown sugar, sesame oil, and minced garlic. Whisk until smooth and pourable.

Heat a skillet over medium-high heat, drizzle in oil. Add chicken, season with salt and pepper, and sauté until golden brown (6-8 minutes); remove and slice.

Return chicken to the skillet, pour the sauce over, and stir to coat evenly. Cook for an additional 2-3 minutes until sauce thickens.

Gently add the drained noodles to the skillet. Toss with tongs until noodles are well-coated and heated through (1-2 minutes).

Transfer to serving bowls and garnish with scallions and sesame seeds. Serve hot.