Begin by cooking the udon noodles according to the package instructions. Once cooked, drain them thoroughly and set aside, ensuring they do not stick together.
In a large skillet or wok, heat the vegetable oil over medium-high heat until shimmering.
Add the minced garlic and grated ginger to the hot oil, sautéing for 1-2 minutes or until fragrant. Be careful not to burn them; stir frequently.
Add the sliced red bell pepper, broccoli florets, and julienned carrot to the skillet. Stir-fry the mixture for about 3-4 minutes, allowing the vegetables to soften slightly yet remain vibrant and crunchy.
Incorporate the cooked udon noodles into the skillet, followed by the soy sauce, oyster sauce, and freshly ground black pepper. Toss everything together gently but thoroughly, ensuring the noodles are well-coated in the sauces and heated through.
Drizzle sesame oil over the noodle mixture and give it another good toss, blending the flavors well.
Remove the skillet from the heat and fold in the chopped green onions, allowing their flavor to infuse into the noodles.
Serve the hot noodles in bowls, garnished with a sprinkle of sesame seeds for an added crunch and visual appeal.
Notes
Adjust the amount of black pepper to taste for desired spiciness.