Bring the millet with sugar, cinnamon and cardamom to the boil and simmer at a low temperature until the grains are almost completely overcooked, stirring occasionally. This takes about 30 minutes.Add more water as needed. It should always remain liquid to mushy, something like rice pudding.
Then add the sultanas and nuts and let stand for another 10 minutes. Add the rose water only at the end.
Spread on dessert bowls and let cool down.
The mass becomes relatively firm at room temperature, like pudding.