Method

• Preheat the oven to 180℃. Grease an 8 or 9-inch springform tins. Grease with butter. Cut out 2 circles of parchment. Lay these on the bottom of the pan. Sprinkle with the 50g extra of sugar. Set aside.
• Slice the citrus fruit of choice and then carefully cut off the rind.
• Lay the fruit on the base of the tin. A little overlap is ok; best not too much though.
• Next up for the cake, cream the butter and sugar for much longer than you think. Much longer, about 6-7 minutes, until the mixture is a pale colour, smooth and almost airy. Having the butter at room temperature will help.
• Then pop in the eggs and aerate by whacking lightly for about a minute. It may curdle a little at this point. That is ok; using a spatula, fold the almonds and polenta in and sieve in the baking powder.
• Add in the zest and juice of the citrus fruit.
• Spoon this mixture over the citrus fruit. Spoon out with a small cranked spatula.
• Bake in the oven for about 40 minutes. The cake is cooked when it is firm to the touch, a skewer comes out clean and the cake begins to move away from the edges of the dish.
• Allow the cake to cool in the tin, and then after about 15 minutes, remove it from the tin and invert onto a plate.
• Make the syrup by heating the juice in a small saucepan. Add in the icing sugar and allow it to dissolve. Allow it to cool a little, Then spoon this over the cake.
• Garnish with a few leaves or springs of thyme.
• Serve with a big dollop of freshly whipped cream.
• Enjoy.