Fry the semolina lightly in the melted butter. Add the baking soda which you've beaten with the yogurt and vanilla.
Mix everything and pour into a buttered baking dish. Bake in a moderate oven until golden.
Cover the cooled cake with syrup, boiled from 2 cups water and 1 1/5 cups (300 g) of sugar.
Serve the cake garnished with cream rosettes and sprinkled with cinnamon.