In a mixing bowl, combine the boneless chicken thighs with garlic powder, onion powder, oregano, thyme, salt, black pepper, and a splash of neutral oil. Mix well to ensure each piece is coated evenly with the seasoning. Allow the chicken to marinate for about 10 minutes.

Heat a large skillet or frying pan over medium heat and add a drizzle of oil. Once hot, place the marinated chicken thighs into the pan, cooking for 5 minutes on each side until they are golden brown and fully cooked through.

In the same pan, melt a tablespoon of butter over medium heat. Add the sliced white parts of the green onions, followed by the mushrooms and minced garlic. Sauté for 3-4 minutes until the mushrooms are softened.

Pour in the chicken stock or dashi stock along with the heavy cream into the pan. Stir the mixture well and then add the white miso paste, ensuring it dissolves completely. Bring the sauce to a gentle simmer for 2-3 minutes.

Return the cooked chicken thighs to the pan, spooning the creamy sauce over them. Let everything simmer together for an additional 3-4 minutes, basting the chicken.

Serve the Creamy Miso Mushroom Chicken Thighs hot with your favorite sides.