1. Preheat the oven to 350°. Spread the almonds on a rimmed baking sheet and toast for about 8 minutes, until golden and fragrant. Let cool.
2. Meanwhile, in a large heatproof bowl set over a saucepan of simmering water, melt the chocolate, stirring frequently, until smooth, about 5 minutes. Remove from the heat and keep warm.
3. In a small bowl, mix the espresso with the sugar until dissolved. Whisk in the rum and stir in the bread cubes; let stand for 5 minutes.
4. Meanwhile, in a large bowl, using a handheld electric mixer, whip the cream until soft peaks form.
5. Spoon half of the soaked bread cubes and any excess chocolate into 6 parfait glasses. Top with half of the whipped cream and half of the almonds. Repeat with the remaining bread and chocolate, whipped cream and almonds. Serve at once.