Melt the butter and broken chocolate in a container in a water bath until the mixture becomes homogenized.
Pull from the heat and stir for another 10 seconds. Add the egg yolks and rum while beating constantly with a mixer.
Once the mixture has cooled slightly, gently stir with the beaten to snow egg whites with the powdered sugar.
Pour the chocolate dessert with rum into small bowls and refrigerate before serving. Serve the dessert decorated with fruit.