Drain morello cherries and steep in rum for 1 day.
Stir butter, powdered sugar & cocoa until smooth. Let the chocolate melt in a bain-marie and cool a little. Stir the chocolate into the fat-sugar mixture. Add almond kernels and rum baking. Leave to cool for about 30 minutes until firm.
Put the mixture into a piping bag with a star-shaped nozzle. Pipe about 40 walnut-sized rosettes onto a baking sheet lined with parchment paper. Form a cherry in the center of each. Leave the truffles to cool for about 1 hour. Melt 400 g white couverture and coat truffles with it. Allow the cooking chocolate to set. Allow remaining cooking chocolate to melt, decorate truffles with it.
Sprinkle with coconut flakes.