Boil milk with vanilla seeds and pod in a pan.
Mix egg yolks, sugar, and cornflour in a bowl.
Pour boiling milk onto egg mixture, return to pan, and boil while stirring.
Remove from heat, discard the pod, and let custard cool.
Whip cream with orange zest and liqueur to soft peaks before folding into custard.
Preheat oven to 220°C.
Boil water, butter, and sugar in a pan for one minute.
Off heat, beat in flour until smooth and pulling away from sides.
Cook mixture over heat for two minutes to cook through.
Cool slightly and beat in eggs one at a time.
Pipe six rounds onto a greased tray and flatten bumps with wet fingers.
Place buns in oven with a cup of water on the bottom shelf.
Cook for five minutes, release steam, and remove water cup.
Bake for 20 minutes until golden.
Pierce bun bottoms with a knife and bake five minutes more to crisp.
Boil sugar and water, then stir in dark chocolate until smooth.
Dust orange segments with sugar and caramelise with a blowtorch.
Pipe cream into buns and serve with oranges and chocolate sauce.