sentence: preheat the oven to 350 degree farenheit and 175 degree celcius sentence: spray 9x12 inch casserole dish with nonstick spray preferably gluten free sentence: in a sauce pan add the evaporated skimmed milk chicken bouillon granules and stir over a medium heat until the milk boils sentence: then add the corn starch slowly and stir for 1-2 minutes or until the mixture thickens sentence: remove it from heat and pour it inot a large mixing bowl to cool down sentence: once it is cooled add the chopped onions grated cheddar yougart salt pepper and melted butter and mix well sentence: pour the sauce mixture over the grated potatoes in a very large bowland mix until everything is well combined sentence: now pour the prepared mix into the ready casserole and top with diced butter sentence: bake for 55 minutes  1 hour when it is done let it set for 15 minutes