Cut the chicken in thin and even thickness and marinate it with seasoning for 10 minutes.
Take some cling film, spread butter and put thyme on it. Then put carrot, celery, and fungus on top of chicken and roll up slowly. Tie the ends of the cling film tightly, and wrap it in aluminum foil.
Steam the wrapped chicken rolls over high heat for 15-20 minutes. Then open and keep the sauce for later use.
Heat a pan with oil, pan-fry the chicken rolls over low heat until golden brown color. Add butter and thyme in the meantime.
Boil the rest of the sauce with seasoning over low heat, then add a little cornstarch water and mix well.
Finally, pour the sauce over the sliced chicken rolls.
Tip:
Cut the chicken in thin and even thickness so that it will be easy to roll up.