Soak gelatin in cold water.
Whisk egg yolk and sugar.
Heat milk and cream, then pour over yolks, stirring constantly.
Return to the pan and cook to 84 °C.
Remove from heat, add gelatin and both chocolates.
Stir until smooth, then pour into 8 Globe mold cavities (leave room for praline).
Freeze for 2 hours, then spoon a layer of hazelnut praline over each.
Freeze overnight.