Whisk butter, sugar and egg.
Sieve flour, baking powder and cacao powder, add with milk and lemon juice to butter-sugar-egg-mixture.
Pour on a baking tray with a baking frame (about 20 x 30 cm) and spread evenly. Or use a baking dish (casserole) with baking paper.
Bake in preheated oven at 170° C for 25 minutes.
Let it cool down.
Cut it in sticks (about 2 x 5 cm)
Put chocolate, coconut fat or oil, milk, icing sugar and rum in a pot and warm up slowly till melted. Stirring to avoid sticking.
Dip the sticks into the chocolate mixture and roll in coconut flakes.
There will be some chocolate dip left. Please don´t through it . You can do: