In a large sauté pan, heat the vegetable oil over medium heat. Add the sliced chicken, grated ginger, minced garlic, and half of the chopped green onions. Cook until the chicken is browned and cooked through, about 5-7 minutes. Remove the chicken from the pan and set it aside.

In the same pan, add the sliced mushrooms and cook until they release their moisture and begin to brown, about 3-5 minutes.

Add the chicken broth, soy sauce, mirin, and sesame oil to the pan. Stir well to combine and bring the mixture to a simmer. Let it simmer for about 10 minutes to allow the flavors to meld together.

Cook the udon noodles according to the package instructions until al dente. Drain and rinse under cold water to remove excess starch.

Add the cooked udon noodles to the broth and toss gently to combine.

Divide the noodles and broth into bowls. Top with the cooked chicken and garnish with the remaining green onions and sesame seeds.

Serve hot and enjoy your Ginger Chicken Udon Noodles!