Begin by freezing the whole cabbage heads for about 3 days; this makes separating the leaves much easier.

Once frozen, thaw the cabbages in the refrigerator overnight until they’re soft enough to peel off the leaves without damage.

In a medium pot, bring water to a rolling boil.

Add your choice of rice, cooking it according to package instructions until it reaches an al dente texture, usually about 10-15 minutes.

Once cooked, drain the rice, rinse it under cold water, and set it aside to cool.

Heat olive oil in a frying pan over medium heat. Add finely chopped onions and sauté until golden and tender, about 5-7 minutes.

Combine the sautéed onions, ground beef, ground pork, cooked rice, grated carrots, chopped parsley, salt, and pepper in a large mixing bowl.

Mix the ingredients thoroughly until everything is evenly distributed.

In a separate bowl, whisk together crushed tomatoes or passata, chicken stock, sour cream, and any additional seasonings.

Take the thawed cabbage leaves, cut away the thick rib at the base, and place about 2 tablespoons of filling on each leaf.

Fold in the sides and roll tightly from the bottom up, ensuring the filling is securely wrapped.

Pour a small amount of the prepared sauce into a baking dish, arrange the cabbage rolls seam-side down, and pour the remaining sauce over them.

Cover and bake in a preheated oven at 350°F (180°C) for 1 hour, then uncover and bake for an additional 30 minutes.