Carrot and Walnut Squares

This is my friend's Sara's recipe. It's easy to make and it's gorgeous!

100-150 g walnuts, chopped
400 g carrots, peeled and grated
200 ml white sugar
200 ml brown sugar
250 ml sunflower oil/rapeseed oil
5 eggs
500 ml flour
1 heaped tsp baking powder
1 tsp bicarbonate of soda
½ tsp salt
1½ tsp ground cinnamon
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300 g cream cheese
100 ml icing sugar
2-3 tbs lime or lemon juice
lime or lemon zest

Use a large baking tin (20x30 cm) and cover the bottom with grease-proof
paper. Butter the sides and cover with breadcrumbs. Heat the oven until 180
degrees C. Mix oil and sugar in a large bowl. Add one egg, mix and add the
second until you've used all five eggs. Add the chopped walnuts and the
grated carrots. In a smaller bowl: mix flour, baking powder, bicarbonate of
soda, salt and cinnamon. Mix these dry ingredients with the others. Pour the
batter into the baking tin. Bake for app. 50 min. Mix the cream cheese with
icing sugar and lime/lemon juice. When the carrot cake is cold, spread the
icing and decorate with lime/lemon zest. Cut into squares.