Place sliced banana over prepared pretzel graham crust.
Divide coconut cream cheese filling among tart pans. Spread into an even layer. Allow to chill in the freezer for 15-30 minutes until cheese cheese filling is cold.
Gently melt dark chocolate over a double boiler, or in the microwave at half power in intervals of 10 seconds. Allow to cool slightly, until just warm to the touch. Chocolate should still be fluid.
Remove tarts from the freezer. Drizzle melted chocolate over coconut cream cheese filling. Immediately sprinkle crushed coconut pretzels over chocolate. Return tarts to freezer and let chill until chocolate is set, about 15-30 minutes.
Unmold tart and serve immediately.