In a saucepan, place the potato and bring to the boil. Simmer over medium heat covered with a lid for 25-30 minutes or until the potato or softened.
In the meantime, heat a sauté pan, over medium heat, and drizzle some oil. Place the chicken skin side down on the pan and sear for 3 minutes. Season well with salt and pepper.
Next, add the onions, garlic, and celery. Continue to sauté for a further 2 minutes, turning the chicken to allow colour on the other side.
Pour in some white wine, and add ¾ of the sweetcorn, mustard, 150ml cream and cream cheese. Season with extra salt and pepper.
Cover with a lid and simmer for 8-10 minutes until the chicken is fully cooked.
Once the potatoes are cooked and soft, drain from the cooking water. Make a mash potato by passing the potato through a potato ricer or masher. Combine with 50ml cream and butter and stir in the rest of the sweet corn and the grated cheese. Check the seasoning and keep warm.
Serve the mash potato with the creamy chicken and sweetcorn sauce.
Sprinkle some oregano and enjoy.