Line a 20.5cm (8in) cake tin with greaseproof paper. Preheat the oven to 190°C (170°C fan) mark 5. Put the sultanas into a pan with the juice of one orange. Bring to the boil and simmer gently until the sultanas are plump and the liquid has been absorbed.
Step 2
Cream the butter, sugar and egg yolks in a bowl until soft and creamy. Add the polenta, ground almonds, soaked sultanas, orange zest and remaining juice. Fold together gently. Whisk the egg whites in a clean, grease-free bowl until soft peaks form. Add a spoonful of the egg whites to the cake mixture to loosen. Fold in remaining whites.
Step 3
Spoon the mixture into the tin and level the top. Bake for 45min until a skewer inserted into the centre comes out clean. For the syrup, heat orange juice, sugar and Grand Marnier in a pan until the sugar dissolves. Bring to boil; simmer for 3-4min to make a syrup. Cool. Prick the cake all over and pour syrup evenly over the top.
Step 4
For the cake topping, beat all the ingredients together in a bowl. Smooth over the cake. Decorate with the orange slices and bay leaves.
An experienced and highly skilled team of food writers, stylists and digital content producers, the Good Housekeeping Cookery Team is a close-knit squad of food obsessives. Cookery Editor Emma Franklin is our resident chilli obsessive and barbecue expert, who spends an inordinate amount of time on holidays poking round the local supermarkets seeking out new and exciting foods. Senior Cookery Writer Alice Shields is a former pastry chef and baking fanatic who loves making bread and would have peanut butter with everything if she could. Her favourite carb is pasta, and our vibrant green spaghetti is her weeknight go-to. Lover of all things savoury, Senior Cookery Writer Grace Evans can be found eating crispy corn and nocellara olives at every opportunity, and will take the cheeseboard over dessert any time (though she cannot resist a slice of tres leches cake). With a wealth of professional kitchen know-how, culinary training and years of experience between them, they are all dedicated to ensuring every Good Housekeeping recipe is the best it can be, so you can trust they’ll work (and if they don’t – we’ll have the answer for why*) every time (*90% of the time the answer is: “buy an separate oven thermometer”!).
