Place the sliced mushrooms in a large, microwave-safe bowl and microwave on HIGH for 5 minutes.Meanwhile, combine the flour with a generous pinch of salt and pepper in a large bowl. Dust the chicken fillets well on both sides with the seasoned flour, shaking to remove any excess (reserve any leftover flour for later), before removing to a plate.Heat the oil and butter in a large, heavy-based saucepan (with a lid) over medium heat, then pan-fry the seasoned chicken for 2-3 minutes per side, or until browned (they don’t have to be fully cooked through), then remove the chicken to a plate.Add the mushrooms to the pan and fry, until lightly browned. Add the leeks, garlic, rosemary, bay leaf, any remaining seasoned flour from earlier to the pan and fry, until fragrant. Add the wine to the pan and use a wooden spoon to scrape up any browned bits from the base of the pan, simmering until the wine stops smelling alcoholic. If not using wine, use the chicken stock in place of the wine.Return the chicken to the pan with the chicken stock and cream. Bring to a simmer, cover and reduce the heat. Cook for 10 minutes, or until the chicken is cooked through and the sauce is thickened. Season the creamy chicken, leek and mushroom stew well with salt and pepper to taste. Sprinkle with parsley, then serve.Photography by Jiwon Kim.Want more from The Cook Up? Stream all the seasons here and for free at