Whisk together the Siúcra/McKinney's Granulated Sugar and egg until light and fluffy.
Combine the dry ingredients and stir them into the mixture, together with the white wine vinegar, margarine and sour milk.
Add the colouring and mix well. Pour the mixture into a greased, floured springform tin about 25 cm in diameter.
Bake in the centre of the oven at 175°C for about 40 minutes.
Leave the cake to cool in the cake tin for a few minutes, then turn out onto a rack to cool completely. Whisk together the cream cheese, lemon juice and Siucra/McKinney's Icing Sugar.
Divide the cake into three layers and spread icing on two of them. Place the two with icing on the bottom, and the one without icing on the top. Cover the entire cake with icing. Decorate with the pralines.