In a bowl, whisk the butter and sugar, without stopping whipping, add one egg at a time.
Add flour, baking powder and coconut flakes. Knead until the dough is smooth.
Stir in the blueberries, zest and lemon juice.
Bake for 35-45 minutes. (Preheat the oven to 180 degrees. I have a square pie shape of 22 cm. If you do not use a silicone mold, then cover it with parchment and oil).
Allow to cool slightly, about 10 minutes, then lay out.