Freeze the Green Cabbage (1 head) overnight and thaw in the morning. Break apart Extra Lean Ground Beef (1 pound) and add Egg (1) and White Rice (3/4 cup) to it. Add Salt (1 1/2 teaspoon), Ground Black Pepper (1 teaspoon), Dried Oregano (1 teaspoon), Dried Parsley (2 teaspoon) and Buttermilk (1/4 cup). Mix them together. After that, Add Onion (1/2 cup) and Mushroom (1/2 cup) and mix them in.
Take the cabbage out of the freezer and peel it apart. Take fourteen leaves. Put some of the filling on each leaf, and fold them in. Roll them up like you would roll an egg roll. Place them into a pan.
In an empty pan on the stove, pour Tomato Sauce (1 cup), Canned Diced Tomatoes (14 ounce), Granulated Sugar (3 tablespoon), Distilled White Vinegar (2 tablespoon). Bring it to boil and add a mix of Corn Starch (2 tablespoon) and Water (1/2 cup). Stir until completely boiled and thickened. After that, turn the heat off and season with Salt and Pepper (to taste).
Pour the sauce over the cabbages, and spread them over. Put them into the oven, preheated to 425 degrees F (220 degrees C) for about 45 minutes to an hour. Take out and serve.