Sift togther four, baking powder and salt; mix in semolina and nuts. Cream butter and sugar until light; add well beaten eggs. Add milk alternately with dry ingredients. Stir after each addition until just smooth. Add a little grated lemon rind and put in a greased square pan. Bake in a moderate oven for about 45 minutes.
Boil the sugar, water, cloves and cinnamon for about 5 minutes and as soon as Halva comes out of the oven pour the syrup on top. Cool and cut into square pieces. If desired, it can be served with whipped cream.