Cream butter and 200 g sugar with the whisk of the hand mixer. Stir in the eggs one after the other. Mix flour and baking powder and stir into the fat mass. Grease a square springform pan (24 x 24 cm), add the dough and smooth it down. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for about 20 minutes
Bring lime juice and blueberries to the boil with juice. Mix starch with 2 tablespoons of water and bind the blueberries with it. Mix grated coconut and 40 g sugar with double cream. Remove the base from the oven. Spread the blueberry compote on the base and spread the coconut mixture flaky on top
Bake again at the same temperature, 2nd rail from the top for about 15 minutes. Remove from the oven, let it cool down and remove from the pan. Cut into approx. 48 rectangles (approx. 2 x 6 cm)