You will need a 23 inch loose-bottomed, spring-release cake tin – Lined with baking paper for this recipe.Pre-heated oven at 160 degree C (fan oven). Start by lining the bottom of the tin with the baking paper.
Using a clean paper towel, spread 50g of the softened butter on top of the baking paper in the tin.
Arrange the sliced orange slices, starting from the middle and working towards the edges, overlapping as needed to cover the bottom of the tin. Set to one-side while you make the cake mixture.
Cream the remaining softened butter and xylitol together in a bowl using a wooden spoon or electric whisk.Add the beaten eggs and yoghurt and whisk until incorporated. Next, gradually whisk in the spelt flour, ground almonds, desiccated coconut and baking powder until you reach a smooth batter consistency.
Gently pour the batter on top of the arranged orange slices and spread evenly. It may help to pour the mixture in 4 sections and using a spatula to gently smooth the batter over the oranges, so as not to disturb them.
Bake in a pre-heated oven at 180 degree C (160 degrees fan oven) for 45mins. Place a piece of foil over the cake during the last 10-15mins if it begins to brown too much.
Remove from the oven, allow to cool for 15mins.Once cooled, release the spring-release and lift away the edges from the tin. Place a plate on top of the cake and quickly turn the cake so that the oranges are now on the top. Carefully peel the baking paper off to reveal the cake.
Best eaten on day of making. If you store any uneaten cake in the fridge and find it has soaked up the juice from the orange slices, you can re-heat the cake for10-15mins to help dry it out again.