Warm up a griddle, or heavy based fry pan. Meanwhile cut the Chicken breast into thick slices across the width. Add to the warmed pan with NO oil. (They should “ hiss” when they hit the pan.)Cook gently, turning often, to brown both sides and cook through.
Meanwhile, slice and dice the Chestnut Mushrooms into small pieces, and put in a small pot with the teaspoon of oil and about a tablespoon of water, to prevent burning/ sticking. Cool on a medium heat until soft but not squishy and almost dry.
Cook the packet rice as per instructions, and then tip onto a plate. Add the cooked chicken to one side. Pour the cooked mushrooms over the rice, to absorb any excess liquid, and mix slightly if wanted. Enjoy!!
