Cut the cabbage in 1 cm large slices.
Gently brown in a pan the oil with the finely chopped onion, garlic and rosemary.
Add the chopped cabbage, salt and pepper and cook on a VERY LOW heat and with the pan covered by a lid, so the vegetables can cook in their own steam.
Stir every now and then to mix the cabbage well.
Once the cabbage is almost cooked, remove completely the lid to dry any excess liquid. Once cooked, sprinkle with nutmeg and serve.