Place the whole cabbage head in the freezer overnight, then thaw and peel off about 8 soft, flexible leaves.
1 small cabbage head
Heat the olive oil in a skillet, sauté the diced onion until golden, then add the grated carrot and cook for 3–4 minutes until soft.
½ cup carrot, finely grated, 1½ tbsp olive oil, ½ medium onion, finely diced
Combine the mashed potatoes, sautéed onion, carrot, breadcrumbs, parsley, salt, and pepper in a large bowl and mix until the filling holds its shape.
1⅓ cups mashed potatoes, 2 tbsp breadcrumbs, 2 tbsp parsley, finely chopped, ½ tsp salt, or to taste, ¼ tsp black pepper, or to taste
Place one cabbage leaf inside a small bowl, add ¼ cup (50g) of filling, fold the edges inward to form a “bomb,” and flip seam-side down; repeat with the rest.
Warm the olive oil in a skillet, toast the tomato paste lightly, pour in the water, add salt, and simmer for 2 minutes.
1½ tbsp tomato paste, 1½ cups water, 2 tbsp olive oil, ½ tsp salt, or to taste
Arrange the cabbage bombs seam-side down in a baking dish, pour the sauce over them, cover with a lid, bake at 190°C (375°F) for 30 minutes, then remove the lid and bake for another 10–15 minutes until lightly golden.
Spoon some sauce over the cabbage bombs and serve warm.