Put the butter and sugar in a mixing bowl and whisk until light and creamy. Add the eggs one at a time, whisking after each addition. Sift in the flour and cinnamon, add the ground almonds and whisk again. Spoon the batter into the prepared tin/pan and level the surface.
Arrange the plums, cut side up, over the top of the cake, scatter over the blueberries and sprinkle with the sugar.
Bake in the preheated oven for 1.5 to 2 hours, until the cake is firm to the touch and a knife inserted into the middle of the cake comes out clean.
Remove from the oven and let cool in the tin/pan for 10 minutes, then turn out onto a wire rack to cool completely. Dust with icing sugar/ confectioners sugar and serve with whipped cream.
This cake will keep for up to 3 days if stored in an airtight container.
Notes
You will also need a 25cm/10inch springform tin/pan greased and lined. Recipe reproduced with permission from The Gluten Free Baker by Hannah Miles, published by Ryland Peters & Small.Can be served with whipped cream or ice cream.