Take egg, sugar and oil in a bowl and beat it properly. Stir in carrot, raisins and pecans.
Sift in flour and bicarbonate of soda. Add cinnamon, nutmeg, mixed spices and salt.
Fold everything in, very gently, with a rubber spatula, dun whisk or stir, otherwise too much air will get incorporated and u will get very heavy carrot cake. Instead of a fluffy one.
Rub butter on the inside surface of the baking tray and line it with a baking parchment and pour the mixture in.
Oven is preheated at 150 degrees for 15-20 min, it will take an hour or quarter of an hour. To check if it is done insert a skewer at the center of the cake, skewer will come out clean if it is done, otherwise pop it into oven again for 5-10 mins. After it is done let it rest for a while on a cooling rack, then serve.
For the icing beat everything together till a smooth mixture and when cake is cool, spread it on the cake. Finely chop some walnuts and sprinkle on top.