Peel and cut potatoes into bite-sized chunks so they all cook evenly. Place in a pot with cold water over high heat. Once boiling, turn the heat down to a simmer. Check the potatoes by inserting a fork into them, once the fork slides in and out with ease, take off of the heat and strain out all of the water.
In a saucepan, bring the broth, thyme, and gravy mix to a low simmer to build flavor. Season with salt and pepper. (Once deep flavor has built, thicken the gravy using 1 teaspoon of flour dissolved in an equal amount of water until smooth and not lumpy). Turn up the heat to a simmer, stir in the mixture a little at a time until it thickens into a gravy. Then set aside and cover with a lid to keep warm. Reheat if needed before serving.
In a saucepan, melt the butter. Once the butter is melted, stir in the cream to warm and then remove from the heat and set aside.
Heat the oil in a skillet or sauté pan to 350°F. Mix the flour and cornstarch. Toss the chicken in the flour/cornstarch then dip in milk, then back into the flour cornstarch to coat well on each side. Once the oil is hot, fry the chicken to a deep golden brown and to an internal temperature of 160°F. Remove from the oil to a paper towel-lined plate to drain excess grease and immediately season with salt. Let rest for 3 minutes before cutting into bite sized pieces.
Using a ricer or potato masher, mash the potatoes to break them up. Mix in the cream and butter mixture, and whip until smooth. Season with salt and pepper to taste.
Place the mashed potatoes in a bowl, top with cheese, chicken, corn, and gravy over top. Garnish with scallions.