I'm sure you could substitute lemon juice in this one, tis yummy
Frosted Orange Squares
Makes 20
225g (8 oz) butter, melted or 250ml (8 fl oz) vegetable oil
300 ml (1/2 pint) unsweetened orange juice
275g (10 oz) caster sugar
2 eggs beaten
400g (14 oz) self-raising flour
Topping
100g (4oz) icing sugar
3 tablespoons unsweetened orange juice
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Pre : 10 minutes
Cooking time : 1 hour
Oven : 180 C, 350 F, Gas Mark 4
Grease and bottom line a 20cm x 25 cm (8 x 10 inch) roasting/baking tin
Place all the cake ingredients in a bowl, beat well until smooth and evenly mixed
To make topping, place icing sugar and orange juice in a bowl and beat together until smooth.
Pour topping over cake when cooked, but still warm and leave in the tin to cool completely.
When cold, cut into squares.