For the chicken, several ways you can cook the chicken. Boil the chicken, think thighs and legs for the most flavor, skin on bone in, or you can use breasts. OR you can bake the chicken in the oven and use that. Boiling will give you broth for use in other recipes. I would go with 1 kilo of chicken, cook, and dice, anything extra, save for use in maybe an omelet or two or for condensed cream of chicken soup from a shortcut. Before you dice, remove all skin, bone, and cartridge.
Preheat your oven to 190 C. Lightly butter a 9x13 baking dish.
In a large bowl, mix together the soup, sour cream, and 1 cup of milk, mix well. Stir in the chicken, salt, and pepper. Pour into the baking dish.
Wipe out the bowl used and now add and mix together the Bisquick mix, cornmeal, egg, and remaining 3/4 cup of milk. Spoon this over the chicken. Sprinkle with the cheese and bake for 30-35 minutes or until the edges are golden brown and the casserole is hot. Let rest for 5 minutes, serve.