Begin by heating 2 tablespoons of sesame oil in a large Dutch oven over medium-high heat. Once the oil shimmers, add your beef chuck roast cut into chunks, searing them for about 4-5 minutes on each side until a rich brown crust forms.

Reduce the heat to medium and add 4 cloves of minced garlic and 1 tablespoon of grated fresh ginger to the pot, sautéing for 1-2 minutes until fragrant. Stir in ½ cup soy sauce, ¼ cup brown sugar, 2 tablespoons rice vinegar, 2 tablespoons gochujang, 1 teaspoon red pepper flakes, and 1 cup beef broth.

Cover the Dutch oven with its lid, reduce the heat to low, and let the mixture simmer for about 3 hours. Stir occasionally to ensure even cooking.

If you prefer a thicker sauce, mix 1 tablespoon of cornstarch with 2 tablespoons of cold water to create a slurry. During the last 10 minutes of cooking, stir in the cornstarch mixture.

Once the beef is perfectly tender, use tongs to shred it directly in the pot. Serve garnished with sliced green onions and toasted sesame seeds.