Make the choux pastry

• Bring the water, butter, salt and sugar to a boil in a saucepan.
• Off the heat, add the flour and beat until the dough pulls away from the pan.
• Return to the heat briefly to dry the dough, then cool slightly.

Beat in the eggs

• Add the eggs one at a time, beating well after each addition.
• Stop when the dough is smooth, glossy and holds a soft peak.

Pipe and bake the rings

• Pipe the dough into rings on a lined baking tray.
• Scatter the flaked almonds over the rings.
• Bake until puffed and golden, then cool on a rack.

Cook the vanilla pastry cream

• Heat the milk in a saucepan.
• Whisk the egg yolks, cornstarch and caster sugar in a bowl.
• Pour the hot milk over the yolks, return to the pan and cook, stirring, until thickened.
• Stir in the vanilla extract and cool completely.

Make the pecan praline cream

• Blitz the toasted pecans with the praline paste until smooth.
• Fold the pecan praline into the cooled pastry cream.
• Whip until light and pipeable.

Assemble the Paris-Brest

• Cut the cooled choux rings in half horizontally.
• Pipe the pecan praline cream generously over the bases.
• Replace the tops and dust with icing sugar.