Do sub the blackberries for other soft fruits you have to hand, this works really well with frozen fruit too.
150g unsalted butter
80g coconut sugar
1 tsp vanilla
160g Buckwheat flour
100g almond flour
1 tsp ground cinnamon
2 tsp baking powder
Plus 1 tbsp sugar, butter and tsp ground cinnamon for topping
Preheat the oven to 170.
Cut the apples and core them, if you really must peel them do, but I much prefer the skins on for aesthetics and for the added fibre that feeds our gut bugs (also time-saving, what’s not to love). Slice into 1/8ths and put all the apple pieces into a bowl of cold water with a spritz of lemon juice to stop them oxidising and going brown ahead of their time.
Blend together the softened butter and sugar, until smooth. Add the whisked eggs and vanilla extract.
Combine the flours, cinnamon and baking powder in a bowl together, and then sift into the butter mixture, just until thoroughly mixed. You don't want it to be over-worked and toughened.
Grease / line an 8inch cake tin. Scrape the batter into it, and decorate with the apple slices, pushing the pieces slightly into the mixture, and then adding blackberries as you fancy.
With the remaining butter, cubed, dot evenly over the fruit and sprinkle over the sugar and cinnamon.
Bake for 30-40 minutes until risen and golden and a skewer comes out clean.