01 - 
                Bring a large pot of water to a boil. Remove the core from the cabbage and place the whole cabbage in the pot. Blanch for 2-3 minutes, then carefully remove the outer leaves as they soften. Set them aside to cool.
              
              
              
                02 - 
                In a large bowl, mix the ground beef, pork, rice, onion, garlic, and egg. Season with salt and pepper, then combine everything well.
              
              
              
                03 - 
                Soak the dried mushrooms in hot water for about 15 minutes to soften, then chop them finely. In a skillet, melt the butter over medium heat, add the fresh mushrooms, and sauté until golden. Stir in the flour and cook for about 1 minute to make a roux. Slowly add water while stirring to avoid lumps. Add the mushroom stock cube, chopped dried mushrooms, and sour cream. Season with salt and pepper, and let simmer until thickened.
              
              
              
                04 - 
                Place about 2 tablespoons of the meat mixture on each cabbage leaf, fold in the sides, and roll up tightly. Place the rolls seam-side down in a large casserole dish.
              
              
              
                05 - 
                Pour the mushroom sauce over the cabbage rolls in the dish. Cover with foil and bake in the oven at 350°F (175°C) for about 1 hour and 30 minutes, until the rolls are cooked through and tender.
              
              
              
                06 - 
                Serve the Gołąbki hot with a generous spoonful of mushroom sauce on top. Enjoy with mashed potatoes or crusty bread on the side.