Step 1

Mix flour, butter, sugar, yeast, and salt together in a large bowl; pour in warm water. Stir mixture into a soft ball. Roll dough out on a floured surface; knead until dough is elastic, 3 to 4 minutes. Place dough in a bowl and cover with a towel; allow to rise in a warm and dry area, about 1 hour.

Step 2

Preheat oven to 350 degrees F (175 degrees C).

Step 3

Heat a large skillet over medium-high heat. Cook and stir beef and onion in the hot skillet until beef is browned and crumbly, 5 to 10 minutes; drain and discard grease. Add cabbage; cook until cabbage is steamed and wilted, about 10 minutes. Season with garlic powder, salt, and pepper.

Step 4

Split dough in half. Roll each piece to fit an 8x8-inch baking dish. Press one of the crusts into the bottom and up the sides of the baking dish. Spoon hamburger mixture into crust; cover with cheese slices. Cover cheese layer with second crust; pinch edges of both crust together to seal.

Step 5

Bake in the preheated oven until lightly browned, about 20 minutes. Cover casserole with aluminum foil and bake until filling is hot, about 10 minutes more. Allow to sit for about 5 minutes before cutting.